Methods of Making Fire Retardant Panel Compositions

ABSTRACT

A fire retardant structural board is provided that includes a body of fibrous material, a triglycidyle polyester binder, a sodium borate pentahydride fire retardant, and a sodium borate pentahydride fire retardant. The body of fibrous material has a weight, first and second surfaces, first and second sides, and a thickness. The fibrous material and triglycidyle polyester are dispersed throughout the thickness of the body. The sodium borate pentahydride fire retardant is dispersed between individual fibers of the fibrous material and throughout the thickness of the body. A sodium borate pentahydride fire retardant composition also coats at least the first surface of the body.

RELATED APPLICATIONS

The present application is a continuation application of U.S. patentapplication Ser. No. 11/650,075 filed on Jan. 5, 2007 entitled FireRetardant Panel Composition and Methods of Making Same which is acontinuation-in-part application of U.S. application Ser. No.11/305,745, filed on Dec. 16, 2005, entitled Fire Retardant PanelComposition and Methods of Making Same which claims priority to U.S.Provisional Patent Application Ser. No. 60/637,020, filed on Dec. 17,2004, entitled Fire Retardant Panel Composition. The disclosures of allof these applications to the extent not explicitly disclosed herein isexpressly incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to fiber mats, boards, panels, laminatedcomposites, structures, and processes of making the same. Moreparticularly, a portion of the present disclosure is related to fireretardant structural boards and methods of making the same.

BACKGROUND AND SUMMARY

Industry is consistently moving away from wood and metal structuralmembers and panels, particularly in the vehicle manufacturing industry.Such wood and metal structural members and panels have high weight tostrength ratios. In other words, the higher the strength of the wood andmetal structural members and panels, the higher the weight. Theresulting demand for alternative material structural members and panelshas, thus, risen proportionately. Because of their low weight tostrength ratios, as well as their corrosion resistance, suchnon-metallic panels have become particularly useful as structuralmembers in the vehicle manufacturing industry as well as officestructures industry, for example.

Often such non-metallic materials are in the form of compositestructures or panels which are moldable into three-dimensional shapesfor use in any variety of purposes. It would, thus, be beneficial toprovide a composite material structure that has high strength usingoriented and/or non-oriented fibers with bonding agents havingcompatible chemistries to provide a strong bond across the composite'slayers. It would be further beneficial to provide a manufacturing andfinish coating process for such structures in some embodiments.

It will be appreciated that the prior art includes many types oflaminated composite panels and manufacturing processes for the same.U.S. Pat. No. 4,539,253, filed on Mar. 30, 1984, entitled High ImpactStrength Fiber Resin Matrix Composites, U.S. Pat. No. 5,141,804, filedon May 22, 1990, entitled Interleaf Layer Fiber Reinforced ResinLaminate Composites, U.S. Pat. No. 6,180,206 B1, filed on Sep. 14, 1998,entitled Composite Honeycomb Sandwich Panel for Fixed Leading Edges,U.S. Pat. No. 5,708,925, filed on May 10, 1996, entitled Multi-LayeredPanel Having a Core Including Natural Fibers and Method of Producing theSame, U.S. Pat. No. 4,353,947, filed Oct. 5, 1981, entitled LaminatedComposite Structure and Method of Manufacture, U.S. Pat. No. 5,258,087,filed on Mar. 13, 1992, entitled Method of Making a Composite Structure,U.S. Pat. No. 5,503,903, filed on Sep. 16, 1993, entitled AutomotiveHeadliner Panel and Method of Making Same, U.S. Pat. No. 5,141,583,filed on Nov. 14, 1991, entitled Method of and Apparatus forContinuously Fabricating Laminates, U.S. Pat. No. 4,466,847, filed onMay 6, 1983, entitled Method for the Continuous Production of Laminates,and U.S. Pat. No. 5,486,256, filed on May 17, 1994, entitled Method ofMaking a Headliner and the Like, are all incorporated herein byreference to establish the nature and characteristics of such laminatedcomposite panels and manufacturing processes herein. It would bebeneficial to provide a structural board that has fire retardantproperties, as well as provide methods of making the panel.

An illustrative embodiment of the present disclosure provides alow-density fire retardant structural board which comprises a body offibrous material, a binder and fire retardant agent. The body of fibrousmaterial includes a weight, first and second ends, first and secondsides and a thickness. The fibrous material is dispersed throughout thethickness of the body. The binder is dispersed throughout the thicknessof the body. The fire retardant agent is dispersed between individualfibers of the fibrous material and throughout the thickness of the body.

In the above and other embodiments, the fire retardant structural boardmay further comprise: the fire retardant agent comprising borate; thefire retardant agent comprising phosphate; the binder being an epoxy;the fibrous material being a natural fiber material; the fibrousmaterial being a synthetic fiber material; the structural board beingrated at least Class B according to ASTM International Fire Test E-84;the fire retardant agent being in a concentration from about 5% to about30% based on the weight of the body of fibrous material; the binderbeing in a concentration from about 5% to about 30% based on the weightof the body of fibrous material; the body further comprising a surfacehaving a fire retardant composition applied thereon; any portion of thesurface that is to be exposed to flame, be completely coated with theapplied fire retardant composition; the applied fire retardantcomposition comprising a borate in a concentration from about 10% toabout 40% based on the weight of the body of fibrous material; and thefire retardant composition comprising a phosphate in a concentrationfrom about 10% to about 50% based on the weight of the body of fibrousmaterial.

Another illustrative embodiment of the present disclosure provides alow-density fire retardant structural board which comprises a body offibrous material, a binder, a fire retardant agent, and a fire retardantcomposition. The body of fibrous material has a weight, first and secondends, first and second sides, first and second surfaces, and athickness. The fibrous material is dispersed throughout the thickness ofthe body. The binder is dispersed throughout the thickness of the body.The fire retardant agent dispersed between individual fibers of thefibrous material and throughout the thickness of the body. The fireretardant composition is applied to the first surface of the body.

In the above and other embodiments, the fire retardant structural boardmay further comprise: the fire retardant composition being applied tothe second surface of the body; wherein the fire retardant agentcomprising a borate; the fire retardant agent comprising a phosphate;the binder being an epoxy; the structural board being rated at leastclass A according to ASTM International Fire Test E-84; the fireretardant agent being in a concentration from about 5% to about 30%based on the weight of the body of fibrous material; the binder being ina concentration from about 5% to about 30% based on the weight of thebody of fibrous material; the applied fire retardant compositioncomprising a borate that is in a concentration from about 10% to about40% based on the weight of the body of fibrous material; the fireretardant composition comprising a phosphate that is in a concentrationfrom about 10% to about 50% based on the weight of the body of fibrousmaterial; and any portion of the surface that is to be exposed to flame,be completely coated with the applied fire retardant composition.

Another illustrative embodiment of the present disclosure provides amethod of manufacturing a low-density fire retardant structural board,the method comprising the steps of: providing a structural mat having aweight, thickness, first and second surfaces, and comprising a fibrousmaterial dispersed throughout the thickness of the mat; applying abinder into the thickness of the mat from the first surface of thestructural mat; applying a fire retardant material into the thickness ofthe mat from the first surface of the structural mat; heating thestructural mat; applying a binder into the thickness of the mat from thesecond surface of the structural mat; and applying a fire retardantmaterial into the thickness of the mat from the second surface of thestructural mat to cure the fire retardant material.

In the above and other embodiments, the fire retardant structural boardmay further comprise the steps of: blowing the binder and the fireretardant material onto the mat, and applying a vacuum underneath themat opposite the blown binder and fire retardant material to draw thebinder and the fire retardant material into the thickness of the mat;heating the structural mat by applying hot air at about 350 degrees F.for about 30 seconds; facing the first surface of the mat upward;further comprising the steps of rotating the mat so the second surfaceof the mat faces upward; collecting the binder and fire retardantmaterial not applied at the first surface of the mat, and applying themto the second surface of the mat; using the binder and fire retardantmaterial collected and not used on first surface of the mat; blowing thebinder and fire retardant material onto the second surface of the mat;applying a vacuum underneath the mat and opposite the blown binder andfire retardant material to draw the binder and the fire retardantmaterial into the thickness of the mat; applying a liquid fire retardantmaterial to the mat and curing the liquid fire retardant material;providing the liquid fire retardant material with a borate that is in aconcentration from about 10% to about 40% based on the weight of thebody of fibrous material; and providing the liquid fire retardantmaterial with a phosphate that is in a concentration from about 10% toabout 50% based on the weight of the body of fibrous material.

Another illustrative embodiment of the disclosure provides a fireretardant structural board comprises a body of natural fibrous material,a triglycidyle polyester binder, a sodium borate pentahydride fireretardant, and a sodium borate pentahydride fire retardant. The body ofnatural fibrous material has a weight, first and second surfaces, firstand second sides, and a thickness. The natural fibrous material andtriglycidyle polyester are dispersed throughout the thickness of thebody. The sodium borate pentahydride fire retardant is dispersed betweenindividual natural fibers of the natural fibrous material and throughoutthe thickness of the body. A sodium borate pentahydride fire retardantcomposition also coats at least the first surface of the body.

In the above and other embodiments, the fire retardant structural boardmay further comprise: the triglycidyle polyester comprising calciumcarbonate and 1,3,5-triglycidyle isocyanurate; the amount of sodiumborate pentahydride being 30% or more of the total weight of the board;about 67% by weight sodium borate pentahydride being dispersed betweenindividual natural fibers throughout the thickness of the body, andwherein about 33% may be applied to at least the first surface of thebody; the sodium borate pentahydride fire retardant composition being anaqueous composition which also includes a surfactant, an adhesive, andwater; the aqueous composition further comprising about 40% sodiumborate pentahydride as dry solids, about 1% surfactant, about 1%adhesive, and the balance water; the triglycidyle polyester binder beinga resin formulated to be about 5% to about 40% of the weight of thenatural fibrous material; about 50% to about 100% natural fibrousmaterial, and comprising about 0% to about 50% synthetic fiber having amelting temperature above about 200 degrees; and the triglycidylepolyester binder further comprising a hardener.

Another illustrative embodiment of the present disclosure provides afire retardant structural board comprising a body of natural fibrousmaterial, an epoxy powder resin binder, and a sodium borate pentahydridefire retardant. The body of natural fibrous material has a weight, firstand second surfaces, first and second sides and a thickness. The naturalfibrous material is dispersed throughout the thickness of the body. Theepoxy powder resin binder is dispersed throughout the thickness of thebody. The borate pentahydride fire retardant is dispersed betweenindividual natural fibers of the natural fibrous material and throughoutthe thickness of the body, and applied to at least the first surface ofthe body.

In the above and other embodiments, the fire retardant structural boardmay further comprise the epoxy powder including a triglycidylepolyester.

Another illustrative embodiment of the present disclosure provides amethod of manufacturing a fire retardant structural board, the methodcomprising the steps of: providing a structural mat having a weight,thickness, first and second surfaces, and comprising a fibrous materialdispersed throughout the thickness of the mat; applying a firstapplication of triglycidyle polyester binder and sodium boratepentahydride onto the first surface and into the thickness of thestructural mat; heating the structural mat; applying a secondapplication of triglycidyle polyester binder and sodium boratepentahydride onto the second surface and into the thickness of thestructural mat; heating the structural mat again; compressing the mat toa desired thickness; and coating the first surface of the mat with acomposition that includes sodium borate penta hydride.

In the above and other embodiments, the method of manufacturing the fireretardant structural board may further comprise the steps of: applyingthe first application of triglycidyle polyester binder and sodium boratepentahydride at a rate of about 200 grams per square meter of totalfibrous mat weight, and heating the mat for about 30 seconds at about175 degrees Celsius using a hot air recirculating oven; applying thesecond application of triglycidyle polyester binder and sodium boratepentahydride onto the second surface of the structural mat at rate ofabout 200 grams per square meter of total fibrous mat weight, andheating the resin for about 60 seconds at about 175 degrees Celsius;cooling the structural mat after compressing and before coating; coatingthe second surface of the mat with the composition that includes sodiumborate penta hydride; coating the first surface using a surface sprayapplicator; coating the first surface using a foam generator systemwhich foams the composition of sodium borate pentahydride liquid into anapplicable foam density, and dispersing the foam onto the first surfacewhere the foam collapses at a rate that allows the composition to wickinto the surface of the mat; warming the first surface to solidify thecomposition.

Additional features and advantages of this disclosure will becomeapparent to those skilled in the art upon consideration of the followingdetailed description of illustrated embodiments exemplifying the bestmode of carrying out such embodiments as presently perceived.

BRIEF DESCRIPTION OF DRAWINGS

The present disclosure will be described hereafter with reference to theattached drawings which are given as non-limiting examples only, inwhich:

FIG. 1 is an exploded side view of a laminated hardboard panel;

FIG. 2 is a side view of the laminated hardboard panel of FIG. 1 in anillustrative-shaped configuration;

FIG. 3 is a perspective view of a portion of the laminated hardboardpanel of FIG. 1 showing partially-pealed plies of woven and non-wovenmaterial layers;

FIG. 4 is another embodiment of a laminated hardboard panel;

FIG. 5 is another embodiment of a laminated hardboard panel;

FIG. 6 is another embodiment of a laminated hardboard panel;

FIG. 7 is a perspective view of a honeycomb core laminated panel;

FIG. 8 is a top, exploded view of the honeycomb section of the panel ofFIG. 7;

FIG. 9 is a perspective view of a portion of the honeycomb section ofthe panel of FIG. 7;

FIG. 10 is a perspective view of a truss core laminated panel;

FIG. 11 a is a side view of an illustrative hinged visor body in theopen position;

FIG. 11 b is a detail view of the hinge portion of the visor body ofFIG. 11 a;

FIG. 12 a is a side view of an illustrative hinged visor body in thefolded position;

FIG. 12 b is a detail view of the hinge portion of the visor body ofFIG. 12 a;

FIG. 13 is an end view of a die assembly to compression mold a fibermaterial body and hinge;

FIG. 14 a is a top view of the visor body of FIGS. 11 and 12 in the openposition;

FIG. 14 b is an illustrative visor attachment rod;

FIG. 15 is a perspective view of a wall panel comprising a laminatedpanel body;

FIG. 16 is a work body;

FIG. 17 is a sectional end view of a portion of the work body of FIG. 16showing an illustrative connection between first and second portions;

FIG. 18 is a sectional end view of a portion of the work body of FIG. 16showing another illustrative connection between first and secondportions;

FIG. 19 is a sectional end view of a portion of the work body of FIG. 16showing another illustrative connection between first and secondportions;

FIG. 20 is a side view of a hardboard manufacturing line;

FIG. 21 a is a top view of the hardboard manufacturing line of FIG. 20;

FIG. 22 is a side view of the uncoiling and mating stages of thehardboard manufacturing line of FIG. 20;

FIG. 23 is a side view of the pre-heating stage of the hardboardmanufacturing line of FIG. 20;

FIG. 24 is a side view of the heat, press and cooling stages of thehardboard manufacturing line of FIG. 20;

FIG. 25 is a side view of a laminating station and shear and trim stagesas well as a finishing stage of the hardboard manufacturing line of FIG.20;

FIG. 26 is a top view of the laminating station and shear and trimstages as well as the finishing stage of the hardboard manufacturingline of FIG. 20;

FIG. 27 is a side view of a portion of the laminating station stage ofthe hardboard manufacturing line of FIG. 20;

FIG. 28 is another top view of the shear and trim stages as well as thefinishing stage of the hardboard manufacturing line of FIG. 20;

FIG. 29 is a top view of another embodiment of a laminated hardboardmanufacturing line;

FIG. 30 is a side view of the calendaring stage of the hardboardmanufacturing line of FIG. 29;

FIG. 31 is a diagrammatic and side view of a portion of a materialsrecycling system;

FIG. 32 is a side view of a materials recycling system and laminatedhardboard manufacturing line;

FIG. 33 is a top view of the materials recycling system and laminatedhardboard manufacturing line of FIGS. 31 and 32;

FIG. 34 is a mechanical properties chart comparing the tensile andflexural strength of an illustrative laminated hardboard panel withindustry standards;

FIG. 35 is a mechanical properties chart comparing the flexural modulusof an illustrative laminated hardboard panel with industry standards;

FIGS. 36 a through c are sectional views of the fibrous material layersubjected to various amounts of heat and pressure;

FIG. 37 is a chart showing an illustrative manufacturing process for afire retardant structural board;

FIG. 38 is graphs showing test results; and

FIG. 39 is graphs showing test results.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplification set out hereinillustrates several embodiments, and such exemplification is not to beconstrued as limiting the scope of this disclosure in any manner.

DETAILED DESCRIPTION OF THE DRAWINGS

An exploded side view of a laminated composite hardboard panel 2 isshown in FIG. 1. Hardboard panel 2 illustratively comprises a fasciacover stock 4 positioned as the surface layer of panel 2. Fascia coverstock 4 may be comprised of fabric, vinyl, leathers, acrylic, epoxies,or polymers, etc. It is appreciated, however, that hardboard panel 2 mayinclude, or not include, such a fascia cover.

The laminated composite hardboard panel 2 illustratively comprises afirst sheet of fibrous material layer 6. Fibrous material layer 6illustratively comprises a natural fiber, illustratively about 25 weightpercent hemp and about 25 weight percent kenaf with the balance beingillustratively polypropylene. The fibers are randomly oriented toprovide a nonspecific orientation of strength. Variations of thisfibrous material are contemplated including about 24.75 weight percenthemp and about 24.75 weight percent kenaf combination with about 50weight percent polypropylene and about 0.05 weight percent maleicanhydride. Other such fibrous materials can be used as well, such asflax and jute. It is also contemplated that other blend ratios of thefibrous material can be used to provide a nonspecific orientation ofstrength. It is further contemplated that other binders in place ofpolypropylene may also be used for the purpose discussed further herein.Furthermore, it is contemplated that other fibrous materials which havehigh process temperatures in excess of about 400 degrees F., forexample, may be used as well.

A woven fiber layer 8 illustratively comprises a woven glass with apolypropylene binder, and is illustratively located between the fibrousmaterial layers 6. It is appreciated that other such woven, non-metalfiber materials may be used in place of glass, including nylon, Kevlar,fleece and other natural or synthetic fibers. Such woven fiber providesbi-directional strength. In contrast, the fibrous material layers 6provide nonspecific-directional strength, thus giving the resultingcomposite enhanced multi-directional strength.

Each surface 10 of fibrous material layers 6 that is adjacent to wovenmaterial layer 8 bonds to surfaces 12 of layer 8. A bond is createdbetween fibrous material layer 6 and woven material layer 8 by a hightemperature melt and pressure process as discussed further herein.Because the glass and fibrous layers have compatible binders (i.e., thepolypropylene, or comparable binder), layers 6, 8 will melt and bind,forming an amalgamated bond between the same. Layers 6, 8 havingpolypropylene as a common chain in each of their respective chemistriesmakes the layers compatible and amenable to such three-dimensionalmolding, for example.

It is appreciated that panel 2 may comprise a plurality of fibrousmaterial layers 6, with woven material layers 8 laminated between eachpair of adjacent surfaces 10 and 12, respectively. A pealed view ofhardboard panel 2, shown in FIG. 3, illustrates such combined use ofwoven and nonspecific-directional or randomly-oriented fibers. Therandom fibers 14 make up fibrous material layer 6, whereas the wovenfibers 16 make up the fiber layer 8. Because bulk mass can increase thestrength of the panel, it is contemplated that more alternating fibrousand woven fiber layers used in the laminated composite will increase thestrength of the panel. The number of layers used, and which layer(s)will be the exterior layer(s), can be varied, and is often dictated bythe requirements of the particular application.

Testing was conducted on illustrative hardboard panels to demonstratetensile and flexural strength. The hardboard laminated materialconsisted of a first layer of 600 gram 80 percent polypropylene 20percent polyester fleece, a second layer of 650 gram fiberglass mix (75percent 0.75K glass/25 percent polypropylene and 10 percent maleicanhydride), a third layer 1800 gram 25 percent hemp/25 percent kenafwith 5 percent maleic anhydride and the balance polypropylene, a fourthlayer of the 650 g fiberglass mix, and a fifth layer of the 600 g 80percent polypropylene 20 percent polyester fleece. This resulted in anapproximate 4300 gram total weight hardboard panel.

The final panel was formed by subjecting it to a 392 degrees F. ovenwith a 6 millimeter gap and heated for about 400 seconds. The materialwas then pressed using a 4.0 millimeter gap. The final composite panelresulted in an approximate final thickness of 4.30 millimeter.

To determine such panel's tensile and flexural properties, ASTM D 638-00and ASTM D790-00 were used as guidelines. The panel samples' shape andsize conformed to the specification outlined in the standards as closelyas possible, but that the sample thickness varied slightly, as notedabove. A Tinius Olson Universal testing machine using industry specificfixtures was used to carry out the tests.

Two lauan boards were coated with a gelcoat finish and formed into final2.7 millimeter and 3.5 millimeter thickness boards, respectively. Theseboards were used as a baseline for comparison with the hardboard panelof the present disclosure. Each of the samples was then cut to the shapeand sizes pursuant the above standards. The tensile and flexuralproperties of the lauan boards were determined in the same manner as thehardboard panel above. Once the results were obtained they were thencharted against the results of the hardboard panel for comparison, asshown below and in FIGS. 34 and 35. The results herein represent theaverage over 10 tested samples of each board.

Avg. Tensile Avg. Flexural Avg. Flexural Panel Description Strength -psi Strength - psi Modulus - psi Hardboard panel 8,585 14,228 524,500Industry standard - FRP/2.7 5,883 9,680 1,045,700 mm lauan Industrystandard - FRP/3.5 7,900 8,260 624,800 mm lauan

As depicted by FIG. 2, laminated panel 2 can be formed into any desiredshape by methods known to those skilled in the art. It is appreciatedthat the three-dimensional molding characteristics of several fibroussheets in combination with the structural support and strengthcharacteristics of glass/polypropylene weave materials located betweenpairs of the fibrous sheets will produce a laminated composite materialthat is highly three-dimensionally moldable while maintaining hightensile and flexural strengths. Such a laminated panel is useful for themolding of structural wall panel systems, structural automotive parts,highway trailer side wall panels (exterior and interior), recreationalvehicle side wall panels (exterior and interior), automotive andbuilding construction load floors, roof systems, modular constructedwall systems, and other such moldable parts. Such a panel may replacestyrene-based chemical set polymers, metal, tree cut lumber, and othersimilar materials. It is believed that such a moldable laminated panelcan reduce part cost, improve air quality with reduced use of styrene,and reduce part weight. Such a panel may also be recyclable, therebygiving the material a presence of sustainability.

Another embodiment of a hardboard panel 20 is shown in FIG. 4. Thispanel 20 comprises a fibrous material layer 6 serving as the core, andis bounded by fiberglass layers 22 and fleece layers 24, as shown. Forexample, the fibrous material layer 6 may comprise the conventionalnon-oriented fiber/polypropylene mix as previously discussed, atillustratively 1800 or 2400 g weights. The fiberglass layer comprises a50 weight percent polypropylene/about 50 weight percent maleicpolypropylene (illustratively 400 g/m²) mix. The fleece layer comprisesan about 50 weight percent polypropylene/about 50 weight percentpolyester (illustratively 300 g/m²) mix. The fleece material providesgood adhesion with the polypropylene and is water-proof at ambientconditions. Furthermore, the polyester is a compatible partner with thepolypropylene because it has a higher melt temperature than thepolypropylene. This means the polypropylene can melt and bond with theother layer without adversely affecting the polyester. In addition, themaleic anhydride is an effective stiffening agent having high tensileand flexural strength which increases overall strength of the panel.

It is contemplated that the scope of the invention herein is not limitedonly to the aforementioned quantities, weights and ratio mixes ofmaterial and binder. For example, the fleece layer 24 may comprise anabout 80 weight percent polypropylene/about 20 weight percent polyester(illustratively 600 g/m²) mix. The laminated composite panel 20 shown inFIG. 4 may include, for example, both fleece layers 24 comprising the50/50 polypropylene/polyester mix, or one layer 24 comprising the 50/50polypropylene/polyester mix, or the 80/20 polypropylene/polyester mix.In addition, same as panel 2, the binder used for panel 20 can be anysuitable binder such as polypropylene, for example.

Another embodiment of a laminated hardboard panel 28 is shown in FIG. 5.This panel 28 comprises a fibrous material layer 6 serving as the corewhich is bounded by fleece layers 24, as shown. As with panel 20, thefibrous material layer 6 of panel 28 may comprise the conventional,non-oriented fiber/polypropylene mix as previously discussed, atillustratively 1800 or 2400 g weights. Each fleece layer 24 may comprisean about 50 weight percent polypropylene/about 50 weight percentpolyester (illustratively 300 g/m²) mix, or may alternatively be anabout 80 weight percent polypropylene/about 20 weight percent polyester(illustratively 600 g/m²) mix. Or, still alternatively, one fleece layer24 may be the 50/50 mix and the other fleece layer 24 may be the 80/20mix, for example.

Another embodiment of a laminated hardboard panel 30 is shown in FIG. 6.This panel 30, similar to panel 20 shown in FIG. 4, comprises a fibrousmaterial layer 6 serving as the core which is bounded by fiberglasslayers 22 and fleece layers 24. The formulations for and variations ofthe fleece layer 24, the fiberglass layers 22 and the fibrous materiallayer 6 may comprise the formulations described in the embodiment ofpanel 20 shown in FIG. 4. Laminated panel 30 further comprises acalendared surface 32, and illustratively, a prime painted or coatedsurface 34. The calendaring process assists in making a Class A finishfor automobile bodies. A Class A finish is a finish that can be exposedto weather elements and still maintain its aesthetics and quality. Forexample, an embodiment of the coated surface 34 contemplated herein isdesigned to satisfy the General Motors Engineering standard for exteriorpaint performance: GM4388M, rev. June 2001. The process for applying thepainted or coated finish is described with reference to the calendaringprocess further herein below.

Further illustrative embodiment of the present disclosure provides amoldable panel material, for use as a headliner, for example, comprisingthe following constituents by weight percentage:

-   -   about 10 weight percent polypropylene fibers consisting of        polypropylene (about 95 weight percent) coupled with maleic        anhydride (about 5 weight percent), though it is contemplated        that other couplers may work as well;    -   about 15 weight percent kenaf (or similar fibers such as hemp,        flax, jute, etc.) fiber pre-treated with an        anti-fungal/anti-microbial agent containing about 2 weight        percent active ingredient; wherein the fibers may be pre-treated        off-line prior to blending;    -   about 45 weight percent bi-component (about 4 denier) polyester        fiber; wherein the bi-component blend ratio is about 22.5 weight        percent high melt (about 440 degrees F.) polyester and about        22.5 weight percent low melt polyester (about 240 to about 300        degrees F. which is slightly below full melt temperature of        polypropylene to permit control of polypropylene movement during        heat phase); wherein, alternatively, like fibers of similar        chemistry may also be used; and    -   about 30 weight percent single component polyester fiber (about        15 denier) high melt (about 440 degrees F.); wherein,        alternatively, like fibers of similar chemistry may be used.

Again, such a material can be used as a headliner. This is because theformulation has a higher heat deflection created by stable fibers andhigh melt polypropylene, and by polyester and the cross-linked polymerto the polymer of the fibers. Furthermore, coupled polypropylene hascross-linked with non-compatible polyester low melt to form a commonmelt combined polymer demonstrating higher heat deflection ranges. Theanti-fungal treated natural fiber protects any cellulous in the fiberfrom colonizing molds for the life of the product should the head linerbe exposed to high moisture conditions.

It is appreciated that other formulations can work as well. For example,another illustrative embodiment may comprise about 40 percentbi-component fiber with 180 degree C. melt temperature, about 25 percentsingle component PET-15 denier; about 15 percent G3015 polypropylene andabout 20 percent fine grade natural fiber. Another illustrativeembodiment may comprise about 45 percent bi-component fibersemi-crystalline 170 degree C. melt temperature, about 20 percent singlecomponent PET-15 denier, about 15 percent low melt flow (10-12 mfi)polypropylene and about 20 percent fine grade natural fiber. It isfurther contemplated that such compositions disclosed herein may defineapproximate boundaries of usable formulation ranges of each of theconstituent materials.

A cutaway view of a honeycomb composite panel 40 is shown in FIG. 7. Theillustrated embodiment comprises top and bottom panels, 42, 44, with ahoneycomb core 46 located there between. One illustrative embodimentprovides for a polypropylene honeycomb core sandwiched between twopanels made from a randomly-oriented fibrous material. The fibrousmaterial is illustratively about 30 weight percent fiber and about 70weight percent polypropylene. The fiber material is illustrativelycomprised of about 50 weight percent kenaf and about 50 weight percenthemp. It is contemplated, however, that any hemp-like fiber, such asflax or other cellulose-based fiber, may be used in place of the hemp orthe kenaf. In addition, such materials can be blended at any othersuitable blend ratio to create such suitable panels.

In one illustrative embodiment, each panel 42, 44 is heat-compressedinto the honeycomb core 46. The higher polypropylene content used in thepanels provides for more thermal plastic available for creating a meltbond between the panels and the honeycomb core. During the manufacturingof such panels 40, the heat is applied to the inner surfaces 48, 50 ofpanels 42, 44, respectively. The heat melts the polypropylene on thesurfaces which can then bond to the polypropylene material that makes upthe honeycomb core. It is appreciated, however, that other ratios offiber to polypropylene or other bonding materials can be used, so longas a bond can be created between the panels and the core. In addition,other bonding materials, such as an adhesive, can be used in place ofpolypropylene for either or both the panels and the core, so long as thechemistries between the bonding materials between the panels and thecore are compatible to create a sufficient bond.

A top detail view of the one illustrative embodiment of honeycomb core46 is shown in FIG. 8. This illustrative embodiment comprisesindividually formed bonded ribbons 52. Each ribbon 52 is formed in anillustrative battlement-like shape having alternating merlons 54 andcrenellations 56. Each of the corners 58, 60 of each merlon 54 isillustratively thermally-bonded to each corresponding corner 62, 64,respectively, of each crenellation 56. Such bonds 66 whichillustratively run the length of the corners are shown in FIG. 9.Successive rows of such formed and bonded ribbons 52 will produce thehoneycomb structure, as shown.

Another embodiment of the honeycomb composite panel comprises a fibrousmaterial honeycomb core in place of the polypropylene honeycomb core.Illustratively, the fibrous material honeycomb core may comprise about70 weight percent polypropylene with about 30 weight percent fiber, forexample, similar to that used for top and bottom panels 42, 44,previously discussed, or even a 50/50 weight percent mix. Suchformulations are illustrative only, and other formulations that producea high strength board are also contemplated herein.

A perspective view of a truss composite 70 is shown in FIG. 10. Trusspanel composite 70 is a light weight, high strength panel for use ineither two- or three-dimensional body panel applications. Theillustrated embodiment of truss composite 70 comprises upper and lowerlayers 72, 74, respectively, which sandwich truss member core 76. Eachof the layers 72, 74, 76 is made from a combinationfibrous/polypropylene material, similar to that described in foregoingembodiments. Each layer 72, 74, 76 comprises a non-directional fibrousmaterial, illustratively, about 25 weight percent hemp and about 25weight percent kenaf with the balance being polypropylene. The fibersare randomly oriented to provide a non-specific orientation of strength.Illustrative variations of this fibrous material are contemplated, whichmay include, for example, an approximately 24.75 weight percent hemp and24.75 weight percent kenaf combination with 50 weight percentpolypropylene and 0.05 weight percent maleic anhydride. Other ratios offibrous materials, however, are also contemplated to be within the scopeof the invention. In addition, other fibrous materials themselves arecontemplated to be within the scope of the invention. Such materials maybe flax, jute, or other like fibers that can be blended in variousratios, for example. Additionally, it is appreciated that other bindersin place of polypropylene may also be used to accomplish the utilitycontemplated herein.

The truss core 76 is illustratively formed with a plurality of angledsupport portions 78, 80 for beneficial load support and distribution. Inthe illustrated embodiment, support portion 78 is oriented at ashallower angle relative to upper and lower layers 72, 74, respectively,than support portion 80 which is oriented at a steeper angle. It isappreciated that such support portions can be formed by using a stampingdie, continuous forming tool, or other like method. It is furtherappreciated that the thickness of any of the layers 72, 74, or even thetruss core 76 can be adjusted to accommodate any variety of loadrequirements. In addition, the separation between layers 72, 74 can alsobe increased or decreased to affect its load strength.

Between each support portion is an alternating contact portion, either82, 84. The exterior surface of each of the alternating contact portions82, 84 is configured to bond to one of the inner surfaces 86, 88 oflayers 72, 74, respectively. To create the bond between layers 72, 74and truss core 76, superficial surface heat, about 450 degrees F. forpolypropylene, is applied to the contact surfaces to melt the surfacelayer of polypropylene, similar to the process discussed further herein.At this temperature, the polypropylene or other binder material ismelted sufficiently to bond same with the polypropylene of the core. Inthis illustrative embodiment, contact portion 82 bonds to the surface 86of upper layer 72, and contact portion 84 bonds to the surface 88 oflayer 74. Once solidified, a complete bond will be formed without theneed for an additional adhesive. It is appreciated, however, that anadhesive may be used in place of surface heat bonding.

The outer surfaces of layers 72, 74 may be configured to accommodate afascia cover stock (not shown). Such fascia cover stock may be comprisedof fabric, vinyl, acrylic, leathers, epoxies, or polymers, paint, etc.In addition, the surfaces of layer 72, 74 may be treated with polyesterto waterproof the panel.

An end view of a hinged visor body 90 is shown in FIG. 11 a. Thisdisclosure illustrates a visor, similar to a sun visor used in anautomobile. It is appreciated, however, that such a visor body 90 isdisclosed herein for illustrative purposes, and it is contemplated thatthe visor does not represent the only application of a formed hingedbody. It is contemplated that such is applicable to any otherapplication that requires an appropriate hinged body.

In the illustrated embodiment, body 90 comprises body portions 92, 94and a hinge 96 positioned therebetween. (See FIGS. 11 b and 12 b.) Body90 is illustratively made from a low density fibrous material, asfurther described herein below. In one embodiment, the fibrous materialmay comprise a randomly-oriented fiber, illustratively about 50 weightpercent fiber-like hemp or kenaf with about 50 weight percentpolypropylene. The material is subjected to hot air and to variablecompression zones to produce the desired structure. (See further, FIG.13.) Another illustrative embodiment comprises about 25 weight percenthemp and about 25 weight percent kenaf with the balance beingpolypropylene. Again, all of the fibers are randomly oriented to providea non-specific orientation of strength. Other variations of thiscomposition are contemplated including, but not limited to, about 24.75weight percent hemp and about a 24.75 weight percent kenaf combinationwith about 50 weight percent polypropylene and about 0.05 weight percentmaleic anhydride. Additionally, other fibrous materials are contemplatedto be within the scope of this disclosure, such as flax and jute invarious ratios, as well as the fibers in various other blend ratios. Itis also appreciated that other binders in place of polypropylene mayalso be used for the utility discussed herein.

The illustrated embodiment of body 90 comprises hinge portion 96allowing adjacent body portions 92, 94 to move relative to each other.The illustrative embodiment shown in FIGS. 11 a and b depicts body 90 inthe unfolded position. This embodiment comprises body portions 92, 94having a thickness such that hinge portion 96 is provided adjacentdepressions 98, 100 on the surface body portions 92, 94, respectively.Because body 90 is a unitary body, the flexibility of hinge portion 96is derived from forming same into a relatively thin member, as hereindiscussed below. In such folding situations as shown in FIG. 12 a,material adjacent the hinge may interfere with the body's ability tofold completely. These depressions 98, 100 allow body portions 92, 94 tofold as shown in FIG. 12 a, without material from said body portionsinterfering therewith. As shown in FIG. 12 b, a cavity 102 is formedwhen body portions 92, 94 are folded completely. It is contemplated,however, that such occasions may arise wherein it may not be desired toremove such material adjacent hinge portion 96, as depicted withdepressions 98, 100. Such instances are contemplated to be within thescope of this disclosure.

In the illustrative embodiment shown in FIG. 11 b, hinge portion 96forms an arcuate path between body portions 92, 94. The radii assist inremoving a dimple that may occur at the hinge when the hinge is at about180 degrees of bend. As shown in FIG. 12 b, hinge portion 96 loses someof its arcuate shape when the body portions 92, 94 are in the foldedposition. It is appreciated, however, that such a hinge 96 is notlimited to the arcuate shape shown in FIG. 11 a. Rather, hinge portion96 may be any shape so long as it facilitates relative movement betweentwo connecting body portions. For example, hinge portion 96 may belinear shaped. The shape of the hinge portion may also be influenced bythe size and shape of the body portions, as well as the desired amountof movement between said body portions.

Illustratively, in addition to, or in lieu of, the fibrous materialforming the visor hinge via high pressure alone, the hinge may also beformed by having a band of material removed at the hinge area. In oneillustrative embodiment, a hinge having a band width about ⅛ inch wideand a removal depth of about 70 weight percent of thickness mass allowsthe hinge full compression thickness after molding of about 0.03125inch, for example. The convex molding of the hinge may straighten duringfinal folding assembly, providing a straight mid line edge between thetwo final radiuses. It is contemplated that the mold for the mirrordepressions, etc., plus additional surface molding details can beachieved using this process. It is further anticipated that the coverstock may be applied during the molding process where the cover isbonded to the visor by the polypropylene contained in the fibrousmaterial formulation.

The illustrative embodiment of body 90 includes longitudinally-extendingdepressions 93, 95 which form a cavity 97. (See FIGS. 11 a, 12 a and 14a.) Cavity 97 is configured to receive bar 99, as discussed furtherherein. (See FIG. 14 b.) It is appreciated that such depressions andcavities described herein with respect to body 90 are for illustrativepurposes. It is contemplated that any design requiring such a moldablebody and hinge can be accomplished pursuant the present disclosureherein.

As previously discussed, body 90 may be comprised of low densitymaterial to allow variable forming geometry in the visor structure,i.e., high and low compression zones for allowing pattern forming. Forexample, the panels portion may be a low compression zone, whereas thehinge portion is a high compression zone. In addition, the highcompression zone may have material removed illustratively by a saw cutduring production, if required, as also previously discussed. Thisallows for a thinner high compression zone which facilitates the abilityfor the material to be flexed back and forth without fatiguing, usefulfor such a hinge portion.

An end view of a die assembly 110 for compression molding a fibermaterial body and hinge is shown in FIG. 13. The form of the dieassembly 110 shown is of an illustrative shape. It is contemplated thatsuch a body 90 can be formed into any desired shape. In the illustratedembodiment, assembly 110 comprises illustrative press plates 112, 114.Illustratively, dies 116, 118 are attached to plates 112, 114,respectively. Die 116 is formed to mirror corresponding portion of body90. It is appreciated that because the view of FIG. 13 is an end view,the dies can be longitudinally-extending to any desired length. Thisillustrative embodiment of die 116 includes surfaces 120, 122 andincludes compression zones 124, 126, 128, 130. Zones 124, 126 areillustratively protrusions that help form the depressions 93, 95,respectively, of body 90, as shown. (See also FIG. 11 a.) Zones 128, 130are illustratively protrusions that help form the depressions 98, 100,respectively, of body 90, as shown. (See also FIG. 11 a.) And zone 132is illustratively a form that, in cooperation with zone 134 of die 118,form hinge portion 96.

This illustrative embodiment of die 118 includes surfaces 136, 138 andincludes compression zones 140, 142, 134. Zones 140, 142 areillustratively sloped walls that help form zone 134. (See also FIG. 11a.) Zone 134 is illustratively a peak that, in cooperation with zone 132creates a high compression zone to form hinge portion 96, and,illustratively, depressions 98, 100, if desired. Again, it isappreciated that the present pattern of such zones shown is not the onlysuch pattern contemplated by this disclosure.

In the illustrated embodiment, body 90, in the illustrative form of ahinged visor, is folded as that shown in FIG. 12 a. It is furthercontemplated that during forming the body may be heated by hot air tobring it up to forming temperatures. The heating cycle time may be about32 seconds, and the toll time after clamp for cool down will be around45 to 50 seconds, depending on tool temperature. Furthermore, skins,like a fabric skin can be bonded to the visor during this step.

Another embodiment of the hardboard panel is a low density panel,illustratively, an approximately 2600 gram panel with about 50 weightpercent fiber-like hemp, kenaf, or other fiber material with about 50weight percent polypropylene. Such materials are subjected to hot air toproduce a light-weight, low density panel. The panel material may beneedle-punched or have a stretched skin surface applied thereon for useas a tackable panel, wall board, ceiling tile, or interior panel-likestructure.

A portion of a dry-erase board 150 is shown in FIG. 15. Such a board 150may comprise a hardboard panel 152 (similar to panel 2) pursuant theforegoing description along with a surface coating 154. The surfacecoating, as that described further herein, provides an optimum worksurface as a dry-erase board. Surface coating 154, for example, can be aClass A finish previously described. This illustrative embodimentincludes a frame portion 156 to enhance the aesthetics of board 150. Oneembodiment may comprise a dual-sided board with a low density tack boardon one side and a dry-erase hardboard on the other side.

An illustrative embodiment of a work body in the form of a table top180, is shown in FIG. 16. The view illustrated therein is a partialcut-away view showing the mating of a top 182 to an underside 184. Anillustrative pedestal 186 supports table top 180 in a conventionalmanner. It is appreciated, however, that the table top 180 is shown inan exaggerated view relative to pedestal 186 so as to better illustratethe relevant detail of the table top 180.

In the illustrated embodiment, the periphery 188 of top 182 is arcuatelyformed to create a work surface edging. The top 182 is attached to theunderside 184 via a portion of the periphery 190 of the same mating withthe top 182. Periphery 190 illustratively comprises an arcuate edgeportion 192 which is complimentarily shaped to the interior surface 194of periphery 188 of top 182. Adjacent the arcuate edge portion 192 is anillustrative stepped portion 196. Stepped portion 196 provides a notch198 by extending the underside panel 202 of the underside 184 downwardwith respect to top 182. Notch 198 provides spacing for edge 200 ofperiphery 188. Such an arrangement provides an appearance of a generallyflush transition between top 182 and underside 184. Interior surface 194of periphery 188 and outer surface 204 of periphery 190 can be mated andattached via any conventional method. For example, the surfaces can beionize-charged to relax the polypropylene so that an adhesive can bondthe structures. In addition, a moisture-activated adhesive can be usedto bond the top 182 with the underside 184.

Detailed views of the mating of top 182 and underside 184 is shown inFIGS. 17 and 18. The conformity between peripheries 188 and 190 areevident from these views. Such allows sufficient bonding between top 182and underside 184. The generally flush appearance between the transitionof top 182 and underside 184 is evident as well through these views. Thevariations between illustrative embodiments are depicted in FIGS. 17 and18. For example, top surface 206 is substantially coaxial with levelplane 208 in FIG. 17, whereas top surface 206 is angled with respect tolevel plane 208. It is appreciated, as well, that the disclosure is notintended to be limited to the shapes depicted in the drawings. Rather,other complimentarily-shaped mating surfaces that produce such atransition between such top and bottom panels are contemplated to bewithin the scope of the invention herein.

Such mating of top 182 and underside 184 may produce a cavity 210, asshown in FIGS. 16 through 19. Depending on the application, cavity 210may remain empty, or may contain a structure. For example, FIG. 19 showsan end view of table top 180 with a truss member core support 76illustratively located therein. Truss member core 76 can be of the typepreviously described and be attached to the interior surfaces 194, 212via conventional means, such as an adhesive, for example. Such a corestructure can provide increased strength to table top 180. In fact, suchstrength can expand the uses of the work body to other applications inaddition to a table top. For example, such can be used as a flooring, orside paneling for a structure or a vehicle. It is contemplated thatother such cores can be used in place of the truss member. For example,a foam core or honeycomb core can be used in place of the truss.

An illustrative hardboard manufacturing line 300 is shown in FIGS. 20through 28. Line 300 is for manufacturing laminated hardboard panels ofthe type shown in FIGS. 1 through 3, and indicated by reference numeral2, for example. The manufacturing process comprises the mating of theseveral layers of materials, illustratively layers 6 and 8 (see FIG. 1),heating and pressing said layers into a single laminated compositepanel, cooling the panel, and then trimming same. In the illustrativeembodiment, line 300 comprises the following primary stages: uncoilingand mating 302 (FIG. 22), pre-heating 304 (FIG. 23), heat and press 306(FIG. 24), cooling 308 (also FIG. 24), laminating station (FIGS. 25through 28), and shear and trim 310 (also FIGS. 25 through 28.) A topview of line 300 is shown in FIG. 21. It is appreciated that the line300 may be of a width that corresponds to a desired width of thecomposite material. FIG. 21 also illustrates the tandem arrangement ofeach of the stages 302, 304, 306, 308, 310.

The uncoiling and mating stage 302 is shown in FIG. 22. In theillustrative embodiment, the materials used for forming the compositeare provided in rolls. It is appreciated that the materials may besupplied in another manner, but for purposes of the illustratedembodiment, the material will be depicted as rolls. Illustratively,stage 302 holds rolls of each illustrative layer 6 and 8 in preparationfor mating. As illustrated, stage 302 comprises a plurality of troughs312 through 320, each of which being illustratively capable of holdingtwo rolls, a primary roll and a back-up roll, for example. In oneembodiment, it is contemplated that any number of troughs can be used,and such number may be dependent on the number of layers used in thelaminated body.

For this illustrative embodiment, line 300 is configured to manufacturea laminated composite panel 2 similar to that shown in FIGS. 1 through3. It is appreciated, however, that the utility of line 302 is notlimited to making only that panel. Rather, such a line is also capableof manufacturing any laminated panel that requires at least one of thestages as described further herein. Troughs 312, 316, and 320 eachcomprise a primary roll 6′ and a back-up roll 6″ of layer 6. In thisexample, layer 6 is illustratively a non-oriented fibrous material.Similarly, troughs 314 and 318 each comprise a primary roll 8′ and aback-up roll 8″ of layer 8 which is illustratively the woven fiberlayer. Each roll rests on a platform system 322 which comprises a sensor324 and a stitching device 326. Sensor 324 detects the end of one rollto initiate the feed of the back-up roll. This allows the rolls tocreate one large continuous sheet. For example, once fibrous materialprimary roll 6′ is completely consumed by line 302, and sensor 324detects the end of that primary roll 6′ and causes the beginning ofback-up roll 6″ to join the end of primary roll 6′. This same processworks with primary roll 8′ and back-up roll 8″ as well.

To secure each roll of a particular material together, stitching device326 stitches, for example, the end of primary rolls 6′ or 8′ with thebeginning of the back-up rolls 6″ or 8″, respectively. The stitchedrolls produce a secure bond between primary rolls 6′, 8′ and back-uprolls 6″ and 8″, respectively, thereby forming the single continuousroll. Illustratively, stitching device 326 trims and loop stitches theends of the materials to form the continuous sheet. Also,illustratively, the thread used to stitch the rolls together is madefrom polypropylene or other similar material that can partially meltduring the heating stages, thereby creating a high joint bond in thefinal panel. It is contemplated, however, any suitable threads can beused which may or may not be of a polymer.

Each trough of stage 302 is configured such that, as the material isdrawn from the rolls, each will form one of the layers of the laminatedcomposite which ultimately becomes the hardboard panel. Fibrous materiallayer 6 of primary roll 6′ from trough 312 illustratively forms the toplayer with the material from each successive trough 314 through 320,providing alternating layers of layers 6 and 8 layering underneath, asshown exiting at 321 in FIG. 22. Each roll of material is illustrativelydrawn underneath the troughs exiting in direction 327. The resultinglayered materials exit stage 302 at 321, pass over bridge 328, and enterthe pre-heating stage 304.

Pre-heat stage 304, as shown in FIG. 23, comprises an oven 323 whichforces hot air at approximately 240 degrees F. into the compositelayers. Oven 323 comprises a heater-blower 330 which directs heated airinto composite chamber 332 which receives the material layers. This hotair removes moisture from layers 6, 8, as well as heats the center-mostlayers of the same. Because often such materials are hydrophobic, theremoval of the moisture causes the center of the materials to cool. Theforced heat causes the center to be warmed, even while the moisture isbeing removed.

This pre-heat allows the process to become more efficient during theheat and press stage 306. Stage 308 illustratively comprise aroller/belt system which includes rollers 333 that move belts 335, asshown in FIG. 23. Illustratively, these belts are located above andbelow the panel 2, defining at least a portion of chamber 332. Belts 335assist in urging panel 2 through stage 304 and on to stage 306.

The preheated composite layers exit through opening 334 of stage 304 andenter the heat and press stage 306, as shown in FIG. 24. The pre-heatedcomposite panel 2 enters stage 306 through opening 336 and into chamber337. The heat and press stage 306, uses a progression of increasinglynarrowly-spaced rollers located between heat zones, thereby reducing thevertical spacing in chamber 337. The combination of the heat and thenarrowing rollers reduces the thickness of panel 2 transforming sameinto a laminated composite panel 2 of desired thickness. For example,stage 306 comprises pairs of spaced rollers 338, 340, 342, 344, 346, 348through which the composite layers pass. The rollers are linearly spacedapart as shown in FIG. 24. In one illustrative embodiment, to make a 4millimeter panel, rollers 338 will initially be spaced apart about 15millimeters. Successively, rollers 340 will be spaced apart about 12millimeters, rollers 342 will be spaced apart about 9 millimeters,rollers 344 will be space apart about 6 millimeters, and finally,rollers 346 and 348 will be each spaced apart about 4 millimeters. Thisgradual progression of pressure reduces stress on the rollers, as wellas the belts 350, 352 driving the rollers. Such belts 350, 352 generallydefine the top and bottom of chamber 337 through which panel 2 travels.Because of the less stress that is applied to belts 350 and 352 whichdrive rollers 338, 340, 342, 344, 346, 348, such belts 350, 352 can bemade from such materials as Teflon glass, rather than conventionalmaterials such as a metal. The Teflon belts absorb less heat than metalbelts do, so more of the heat generated will be transferred to the tothe lamination of panel 2, in contrast to production lines usingconventional metal belts. In one illustrative embodiment, stages 306 and308 are approximately 10 meters long and approximately 4 meters wide.

In one illustrative embodiment, located between every two pairs ofrollers are a pair of surfaces or platens 354, 356 between which thepanel 2 moves during the lamination process. Illustratively, platens354, 356 receive hot oil or similar fluid. It is appreciated, however,that other methods of heating the platens can be used. In the presentembodiment, however, the hot oil causes the platens 354, 356 to raisethe core temperature of the panel 2 to about 340 degrees F. Thecombination of the compression force generated by the rollers 338, 340,342, 344, 346, 348 and the heat generated by the platens 354, 356 causesthe polypropylene in the material layers 6, 8 to melt, causing same tobegin fusing and compacting into the panel 2 of desired thickness.

After the layers 6, 8 of the composite panel 2 is heated, fused, andreduced to a desired thickness, the resulting composite panel 2 iscooled at cooling stage 308. In the illustrated embodiment, coolingstage 308 is an extension of the heat and press stage 306 to the extentthat stage 308 also includes pairs of rollers 358, 360, 362, 364, 366which are similarly situated to, and arranged linearly with, rollers338, 340, 342, 344, 346, 348. The space between each of the rollers isabout the same as the space between the last pair of rollers of the heatand press stage 306, in this case rollers 348. In the forgoing example,the rollers 348 were illustratively spaced apart about 4 millimeters.Accordingly, the spacing between the rollers of each pair of rollers358, 360, 362, 364, 366 of stage 308, through which the panel passes, isalso spaced apart about 4 millimeters. Cooling stage 308 treats platens372 through 406 that are cooled with cold water, illustratively atapproximately 52 degrees F., rather than being treated with hot oil, asis the case with heat and press stage 306. This cooling stage rapidlysolidifies the melted polypropylene, thereby producing a rigid laminatedhardboard panel 2.

Hardboard panel 2 exits the cooling stage 308 at exit 408, as shown inFIG. 24, and enters the shear and trim stage 310, as shown in FIGS. 25through 28. In one illustrative embodiment, composite panel 2 passesthrough an interior wall laminating stage 410 and into the trim andcutting stage 412. When panel 2 passes through stage 412, its edges canbe trimmed to a desired width and the panel cut to any desired lengthwith the panel exiting to platform 414.

A top view of line 300 is shown in FIG. 21 which includes the variousaforementioned stages 302, 304, 306, 308, 310 as well as finishing astage 416. This stage 416 is illustratively for applying an acrylic orother like resin finish to the surface of the composite panel.Specifically, once such a composite panel 2 exits the shear and trimstage 310, it is supported on a plurality of rollers 418 and placedalong the length of platform 414 to move panel 2 in direction 420. Inone illustrative embodiment, panel 2 may be rotated into position, asshown in FIG. 28, to finishing stage 416. To rotate panel 2, movablecatches 422, 424, one at the proximal end of platform 414 and the otherat the distal end of platform 414, as shown in FIGS. 21 and 28, bothmove concurrently to move panel 2. Catch 422 moves a corner of panel 2in direction 420 while catch 424 moves the other corner of panel 2 indirection 426, ultimately positioning panel 2 on platform 415 at stage416. It is appreciated, however, that it is not required to locate sucha finishing stage at an angle relative to line 300. Alternatively, stage416 may be located linearly with the remainder of line 300.

Illustratively, before applying the acrylic finish to panel 2 at stage416, its surface is first prepared. The illustrative process forpreparing the surface of panel 2 is first sanding the surface to acceptthe finish coat. After sanding the surface of panel 2, a wet coating ofthe resin is applied. Illustratively, the resin is polyurethane. Theacrylic resin can then be UV cured, if necessary. Such curing iscontemplated to take as much as 24 hours, if necessary. Initial cooling,however, can take only three seconds. Such an acrylic coating hasseveral uses, one is the dry-erase board surface, previously discussed,as well as exterior side wall panels for recreational vehicles and pulltype trailers. It is further contemplated herein that other surfacecoatings can be applied at stage 416 as known by those skilled in theart.

In another illustrative embodiment, interior wall laminating stage 410,though part of line 300, can be used to create wall panel compositesfrom panel 2. When making such panel, rather than panel 2 passingthrough stage 410, as previously discussed panel 2 is laminated at stage410. In this illustrative embodiment, as shown in FIGS. 25 and 26, forexample, stage 412 comprises an uncoiling hopper 430, a hot air blower432, and a roller stage 434. Hopper 430 is configured to supportillustratively two rolls of material. For this illustrative embodiment,a base substrate layer 436, and a finish surface material layer 438 islocated in hopper 430. It is appreciated that the base substrate layer436 can be any suitable material, including the fibrous material layer 6as previously discussed or a priming surface material. The finishsurface material layer 438 can be of any finishing or surface materialsuch as vinyl, paper, acrylic, or fabric. Uncoiling hopper 430 operatessimilar to that of stage 302 to the extent that they both uncoil rollsof material. Hopper 430 operates differently from stage 302, however, tothe extent that both layers 436 and 438 uncoil concurrently, rather thanin tandem, like rolls 6′ and 6″, for example. In other words, bothlayers 436, 438 will form the layers of the composite top coat, ratherthan form a single continuous layer for a board, as is the case withroll 6′ and 6″.

In the illustrative embodiment, base substrate layer 436 uncoils belowthe finish surface material layer 438, as shown in FIGS. 26 and 27. Inaddition, both layer 436 and layer 438 form a composite as they enterroller stage 434. The hot air blower 432 blows hot air 448 atapproximately 450 degrees F. in direction 448 between layer 436 andlayer 438. This causes the surfaces, particularly the base materiallayer 436 surface, to melt. For example, if the base substrate layer 436is fibrous material layer 6, the polypropylene on the surface of thismaterial melts. As layer 436 and layer 438 pass between a pair ofrollers 450 at the roller stage 434, the melted polypropylene of layer436 bonds with the layer 438, forming a composite of fibrous materialhaving the finish surface material 438. After the materials have formeda laminated composite, they can then proceed to the shear and trim stage310.

It is contemplated that finish surface material layer 438 may compriseseveral finish materials applied to base material layer 436 eitherconcurrently or in tandem. For example, a roll of material layer 438 maycomprise a roll that includes a section of vinyl, attached to a sectionof paper, and then fabric, and then vinyl again. Uncoiling this roll andbonding it to layer 436 produces a single composite board having severaltandemly positioned finish surfaces that can be sheared and cut at stage310 as desired.

Another illustrative hardboard manufacturing line 500 is shown in FIGS.29 and 30. Line 500 is another embodiment for manufacturing laminatedhardboard panels of the type illustratively shown in FIGS. 4 through 6.This manufacturing line 500 is similar to manufacturing line 300previously discussed, wherein process 500 comprises the mating ofseveral layers of materials, illustratively layers 22, 24, as well asthe calendaring surface 32 and coated surface 34, as shownillustratively in panel 30 of FIG. 6. Manufacturing line 500 comprisesthe following panel manufacturing stages: the uncoiling and matingstages 502, the pre-heating stage 504, the heat and press stage 506, thecooling stage 508, the calendaring stage 510, and the shear and trimstage 512.

One illustrative embodiment of line 500 comprises a calendaring stage510. This stage is located in the same location as the laminating stage410 of line 300, as shown in FIG. 25. The purpose of the calendaringstage is to smooth the top surface of the illustrative panel 30 toprepare it for the paint application of line 514. Conventionally, usingbelts 350, 352 in conjunction with the heated platens may cause thetexture of those belts, similar to a cloth pattern, to be embedded inthe surfaces of the panel 30. (See, also, FIG. 24.) The calendaringprocess removes this pattern to provide a smoother surface inanticipation of the paint application. In the illustrated embodimentshown in FIG. 30, calendaring stage 510 comprises a conveying line 570and spaced apart rollers 572, as well as a heat source 574. As panel 30exits the cooling stage 508, it is transferred to the calendaring stage510 where the heat source, illustratively infrared heat or heated air,or a combination of both, is applied to the surface of the panel 30.Panel 30 is then directed between the two spaced apart rollers 572 whichwill then smooth the surface that has been heated by heater 574. In oneembodiment, it is contemplated that at least one of the rollers istemperature controlled, illustratively with water, to maintain therollers up to an approximate 120 degrees F. It is further contemplatedthat the heated air or IR heater is controlled to only heat the surfaceof panel 30 and not the center of the board itself. Furthermore, it iscontemplated that the roller can subject up to an approximate 270 poundsper linear inch force on the surface of the panel 30 in order to smoothout any pattern in the surface and/or related defects thereon to producea calendared surface 32 as previously discussed with respect to FIG. 6.It will be appreciated that this calendaring process will prepare thesurface 32 of panel 30 so that it may receive a Class A auto finish.Once the panel 30 exits the calendaring stage 510, it then istransferred to the shear and trim stage 512 where the panel will takeits final shape prior to the paint stage.

In contrast to manufacturing line 300, however, line 500 furthercomprises paint application line 514. Paint line 514 comprises atransfer conveyer 516 which moves panels, in this illustrative casepanel 30, from the shear and trim stage 512 to the paint line 514. Thisis accomplished illustratively by rollers on conveyer 518 moving panel30 perpendicularly from shear and trim stage 512 to paint line 514 whichis illustratively positioned parallel to line 500. If, for example,panel 30 or the other panels 20 and 28 do not receive a paintapplication, they can be removed from the line at an off-load point 520.If panel 30, for example, will be receiving a paint application, it isloaded onto paint line 514 via a staging section 522 as shown in FIG.29. The first stage of the paint process of paint line 514 is to flametreat the top surface of panel 30 at 524. The flame treatment process isa means to relax the surface tension and ionize-charge the board forchemical bonding. This will decrease the surface tension of the plasticor the bonding material. Such decrease in surface tension allows theplastic to have a similar surface tension to that of the paint that willcreate better adhesion of the paint to the board. In the illustrativeembodiment, the flame treatment uses a blue flame approximately ¼ inchin height, and the board is passed below the flame of about ⅜ of an inchat a rate of about 26 feet per minute. It is appreciated, however, thatother means of heating the surface of panel 30 is contemplated and, inregards to the flame size, temperature, and the distance of the boardfrom the flame, is illustrative and not considered to be the soleembodiment of this disclosure.

It is contemplated that much of the paint line will be enclosed and,because of such, after the flame treatment stage 524, an air inputsection is added to create positive pressure within the line. In theillustrative embodiment, a fan is added to this section to input airwhich will blow dust and debris away from the panel to keep it clean.The next stage of paint line 514 is the adhesion promoter spray booth528. Booth 528 applies a plastic primer to the surface of panel 30 thatintegrates with the plastic in the board to assist in better adhesion ofsubsequent paint layers. In this illustrative embodiment, a down-draftspray of the primer is applied to the surface of panel 30. Exiting booth528, another air input section 530 is illustratively located to furthercreate positive pressure to continue preventing dust or othercontaminates from resting on the surface of the panel.

After panel 30 exits the adhesion promoter booth 528, it enters the UVprimer seal spray booth 532. Booth 532 applies a UV filler paint tofurther level the surface of the panel 30, as well as serve as anadditional primer for the final UV care paint. It is appreciated,however, that depending on the application of the panel, the UV fillercan be replaced with a UV paint or other paint as a topcoat. In thisillustrative embodiment, however, the booth 532 uses a down-draft sprayto apply the primer seal onto panel 30.

Exiting booth 528, panel 30 then enters an ambient flash stage 534wherein the panel 30 rests to allow solvents from the paint toevaporate. Though not shown, the solvents are drawn from the ambientflash stage 534 where the solvents are burned so as to not enter theatmosphere. In addition, stage 534 may include an input fan 536, similarto air inputs 526 and 530, to maintain positive pressure in thissection.

After allowing the solvents to dissipate from the surface of the panel30, it is transported under a UV cure lamp 538 to further cure thepaint. The UV cure 538 is illustratively a high-intensity, ultra-violetlight to which the paint is sensitive, and which will further cure thepaint.

After passing through UV cure 538, the panel 30 is passed through aninfrared oven 540. The panel 30 is moved through oven 540 at anillustrative rate of 2.5 meters per minute and the IR oven is set atabout 165 degrees F. This step further assists to drive out anyremaining solvents that might not have been driven out prior to the UVcure. In addition, those solvents are also then sent off and burnedbefore reaching the atmosphere.

Once exiting the IR oven 540, panel 30 is transferred to a side transfersection 542 which allows either removal of panel 30 if the paint appliedat booth 532 was the final application of paint, or through conveyors544 as shown in FIG. 29, if panel 30 is to be transferred to a secondarypaint line 546.

If panel 30 is transferred to secondary paint line 546, it is passedthrough another spray booth 548. Booth 548 uses a down-draft spray toapply a UV topcoat over top the UV filler and adhesion promoter coatspreviously discussed. The UV topcoat will be the finished coat thatprovides the Class A auto finish as previously discussed, for example.Once the topcoat has been applied onto the surface of panel 30, thefollowing process is similar to that as described with respect to paintline 514 which is that the panel 30 is again subjected to an ambientflash at section 550, similar to ambient flash stage 534 previouslydiscussed, wherein the solvents are allowed to evaporate, and are drivenoff and burned. Furthermore, the panel is transferred through a UV cure552 section, similar to that of 538 and as previously discussed, the UVcure 552 serves also as UV high-intensity light to further cure thetopcoat applied at 548. After passing through the UV section 552, panel30 then enters infrared oven 554, which is similar to IR oven 540previously discussed, wherein the panel is subjected to a temperature ofabout 165 degrees F. for about 2.5 minutes.

When panel 30 exits the IR oven, it enters an inspection booth 556 wherethe surface is inspected for defects in the paint or in the board. Theinspection can be either manually accomplished by visual inspection ofthe surface and identifying such defects, or can be accomplished throughan automated inspection process comprising sensors to locate defects,etc. In addition, the inspection booth 556 also serves as a cool-downprocess for the process. The inspection booth 556 maintains atemperature of about 78 degrees F. with about 50 weight percent relativehumidity to cool down at least the surface of the board from theapproximate 165 degrees F. from the IR oven to about 80 degrees F. If aboard does not pass inspection, it will be removed for repair orrecycling. If the board does pass inspection, it will pass through apinch roller 558 that will apply a slip sheet which is illustratively athin 4 millimeter polypropylene sheet that protects the painted surfaceof panel 30 and allow the same to be stacked at the off-load section560.

Composite materials, like those used to manufacture automobile bodiesand interiors, have the potential to be recycled into new materials. Animpediment to such recycling, however, is incompatible particle sizes ofotherwise potentially recyclable constituents. For example, a variety ofcombinations of polypropylene, vinyl, polyester, ABS, and fibrousmaterials may be used to produce a panel or core product for a panel.

In the recycle system 600, shown in FIGS. 31 through 33, severalmaterials are collected and segregated based on a desired composition at602. Each material is granulated to reduce its particle size. The degreeto which each material is granulated can be varied depending on thechemistry desired in the resulting panel. After each material isgranulated, the loss and weight is determined at 604. This is done sothat the cross-section and weight can be controlled before the resultantmaterial is laminated into a panel. The materials are blended into acomposition at 606 and transferred to collector 608. The composition isthen transferred from collector 608 through a metal detector 612 whichis configured to remove metal particles. The remaining composition isthen deposited into a scatter box 614. Scatter box 614 allows particlesof a particular maximum size to deposit onto granulate belt 616. Theloss and weight of the resulting composition is then determined again tomaintain the density of the final panel. The composition is thentransferred to the recycle composition storage 626 in anticipation fordeposit with the other laminate constituents.

The recycled composition manufacturing panel line 618, shown in FIGS. 32and 33, is similar to line 300 shown in FIG. 20. Line 618 comprises thefollowing primary stages: uncoiling 620, pre-heater 622, heat andpressure 624, recycled material storage 626, cooling 628, shear and trim630. In the illustrated embodiment of FIG. 32, rolls 632, 634 ofmaterial, such as a fibrous or woven glass material, for example, arelocated at stage 620. Rolls 632, 634 are uncoiled to form compositelayers. These layers are then pre-warmed using pre-heater stage 622,similar to stage 304 used in manufacturing line 300. The recycledcomposition material from stage 626 exists in the form of chips havingan irregular shape with a maximum dimension in any one direction of,illustratively, 0.125 inches, and is then deposited between thecomposite layers. The new composite layers are then subjected to thesame heat, pressure, and cooling at stages 624 and 628, respectively, asto the heat and press stage 306 and the cooling stage 308 ofmanufacturing line 300.

The heat and pressure stage 624 receives the preheated composite layers,and through a progression of increasingly narrowly-spaced rollers,compresses the composite layers to a desired thickness similar to thatpreviously discussed. Again, this gradual progression of pressurereduces stress on the rollers and the belts driving the rollers, asdiscussed with stage 306 of line 300. In addition, the belts that drivethe rollers can, too, be made of Teflon glass material, rather than ametal, also previously discussed. Also similar to stage 308, stage 628includes a pair of surfaces or platens between every two pairs ofrollers to allow the composite layer to move there between.Illustratively, the platens receive hot oil. It is appreciated thatother methods of heating the platens are contemplated, similar to stage306. After the composite layers are heated, fused, and reduced to adesired thickness, the resulting panel is cooled. Cooling stage 628 iscomparable to stage 308. The final stage is shear and trim 630, which isalso similar to the shear and trim stage 310 of line 300.

As shown in FIGS. 32 and 33, line 618 further includes a dual sidelamination stage 636. Stage 636 is similar to stage 410, shown in FIG.25, except for the additional uncoiling stage 638 located beneath aprimary uncoiling stage 637. It is contemplated that applying a surfaceon both sides of a composite panel is the same as applying a singlesurface, as shown in FIG. 20, with the exception that warm air will bedirected to both sides of the composite panel. The process as shown inFIG. 20 does apply to the lower surface as well.

A sectional view of fibrous substitute material layer 6 is shown inFIGS. 36 a through c. The distinction between the views of FIGS. 36 athrough c is the amount of heat and pressure applied to fibrous materiallayer 6. As previously discussed above, fibrous material layer 6illustratively comprises a mat of illustratively about 25 weight percenthemp and about 25 weight percent kenaf with the balance beingillustratively polypropylene. The fibers are randomly oriented toprovide a nonspecific orientation of strength. Variations of thisfibrous material are contemplated, including an about 24.75 weightpercent hemp and about 24.75 weight percent kenaf combination with about50 weight percent polypropylene and about 0.05 weight percent maleicanhydride. Other such fibrous materials can be used as well, such asflax and jute, for example. It is also contemplated that other blendratios of the fibrous material can be used. It is further contemplatedthat other binders in place of polypropylene may also be used for thepurpose discussed further herein. Still further, it is contemplated thatother fibrous materials which have high process temperatures in excessof about 400 degrees F., for example, may be used as well.

The fibrous material layer 6 shown in FIG. 36 a is considered a virginversion of the layer, similar to that shown in FIG. 1, or on rolls 6′and 6″ shown in FIG. 22. This version of layer 6 is considered virgin,because it has not been subjected to a heat treatment or was compressed.The fibers and the binder that compose the layer exist as essentiallyseparate constituents simply mixed together. In this state, the virginversion is highly permeable and pliable. The relative thickness 700 ofthe layer 6 is relatively greater than the thicknesses 702 or 704 oflayers 6 shown in either FIGS. 7 b and 7 c, respectively. Furthermore,because the binder, polypropylene, for example, is not bound to thefiber, heating layer 6 may cause it to consolidate or shrink,particularly in its length and width.

In contrast, layer 6 shown in FIG. 36 c, though comprising the sameconstituents as layer 6 in FIG. 36 a, has been subjected considerably toheat and pressure. This embodiment of layer 6 is considered a highdensity version. In this case, the binder has been fully wetted-out.Fully wetted-out, for the purposes of this discussion means that thebinder has, for practical purposes, all liquefied and bonded to thefibrous material of layer 6. Such produces an essentially non-permeable,dense and rigid body. The binder, typically a thermal melt polymer, likepolypropylene, is melted into a liquid state, causing the polymers toadhere to and/or wet-out the fibrous materials. This can produce aconsolidation of the composite when cooled which shrinks the layer. Thisresults, however, in a rigid and dimensionally stable flat sheet. Ifsuch a layer is then reheated, because the binder is already bonded withthe fibrous material, the layer will not shrink, unlike the layer 6described in FIG. 36 a. Such high density layers are used to produce thelayers 72, 74 of truss composite 70, previously discussed with respectto FIG. 10, for example.

The version of layer 6 shown in FIG. 36 b, in contrast to both thevirgin and high density versions from FIGS. 36 a and c, respectively, isconsidered a low density version. This low density version has beensubjected to heat and pressure, so that a portion of the binder in thelayer has been wetted-out, unlike the virgin version of FIG. 36 a whichhas not been subjected to such a process. Furthermore, unlike the highdensity layer shown in FIG. 36 c, the binder of the low density layerhas not been fully wetted-out. In other words, not all of the binder inthe low density layer has liquefied and bonded to the natural fibers,only a portion of the binder has. The remaining binder is stillmaintained, separate from the fibrous material. This makes the lowdensity version rigid, similar to the high density version, yet, alsosemi-permeable, more akin to the virgin version. In one illustrativeembodiment, the binder has melted and soaked into about 50 percent ofthe fibers that are in the layer. In this case, it is not believed thatthe fibers per se have grown, nor changed in a specific value. Rather,the fibers have just absorbed the binder.

The low density version can provide accelerated processing forthree-dimensional molding, particularly in molding, like that shown inFIGS. 11 and 12, where various compression zones are used to form thematerial. Furthermore, utilizing such a composite provides lowerproduction costs. In addition, because the layer is rigid, yet has somepermeability, it can be used as a tack board alone or in conjunctionwith the dry erase board 150 of FIG. 15, for example. The propertiesalso make it conducive to acoustical insulation or ceiling tiles.

Conventional heat sources such as infra red ovens are not used to heat ahigh density layer 6 material, because it may cause changes to itsphysical dimensions or cause overheating of the surface area of the highdensity layer 6 in order to bring the core up to proper processingtemperatures. In contrast, contact heating ovens, which use upper andlower heated platens to hold a virgin layer 6 under pressure duringheating to prevent significant shrinkage, are not readily available inthe general molding industry that may use such materials. Furthermore,the target cycle times required to heat these layers to moldingtemperatures require extra energy and equipment.

Using the low density version of layer 6 can, on balance, be a more costeffective way to mold such fibrous material layers. For example, an 1800gram per meter square sample of fibrous material, as described withrespect to FIGS. 26 a through c, may require about 83 seconds of heattime in a contact oven to get the virgin version up to moldingtemperature. The high density version may require 48 seconds of heattime in an IR oven. The low density board, however, may require onlyabout 28 seconds of heat time in an air circulated hot air oven. This isto reach a core temperature of about 340 to 350 degrees F.

When heating the low density version in a simple air circulated hot airoven, the energy required to heat low density board is 50 percent lessthan the required energy to heat the layer through a contact oven and 70percent less than the required energy to heat a consolidated hard boardutilizing infra red oven. The high density layer is typically onlyheated by an infrared oven. This is because the high density versiondoes not have the permeability for hot air, and contact ovens mayoverheat and damage the layer.

Some benefits of the high density version over the virgin version arealso found in the low density version. First of all, similar to how thehigh density version requires less packaging space than the virginbecause of its reduced thickness, the low density version too requiresless packaging space since its thickness is also less than that of thevirgin version. Such translates into reduced shipping costs. Secondly,because the low density version is rigid, like the high density version,the low density version can be handled much easier with mechanicaldevices, such as grippers and clamps. This can be more difficult withthe virgin version which is more pliable. Also, the low density materialdoes not always have to be pre-heated. Some applications of the virginversion may require the layer to be preheated so as to dimensionallystabilize the material. This is not necessary with the low densityversion. In contrast, for those production lines that use a needlesystem to handle materials, particularly, for materials like the virginversion of layer 6, the high density version would not receive suchneedles, because of the solidified binder. The low density version,however, still being semi-permeable, may receive such needles, allowingit to be transported easily, similar to that of the virgin version.

Manufacture of the low density version like that shown in FIG. 36 ccomprises subjecting the virgin version to both heat and pressure. Theheat and pressure is illustratively provided by an oven which comprisescompressed rolls that pinch the material to reduce its ability to shrinkwhile it is being heated. The rolls have belts with holes disposedtherethrough, through which the hot air passes. The layer is being heldas structurally rigid as possible so it does not suck-in and becomenarrow and thick in the middle. The heat and pressure causes the binderto liquefy, and under the rollers, causes the melted binder to beabsorbed into and surround the natural fiber. The layer may shrink tosome minor extent, but that can be compensated for during thismanufacturing process. When the layer is removed from the oven, cold airis blown on it to solidify the layer.

Typically, thermal melt polymers are heat sensitive, and at temperaturesabove 240 degrees F. will attempt to shrink (deform). Therefore, theopposing air permeable belts having opposing pressures limits the amountof heat sink shrinkage that will occur during this process. Once theinitial heating has occurred (polymers changed from a solid to liquidstate), and consolidation of thermal melt and non-thermal melt fibersare achieved, the consolidated layer 6 becomes thermal dimensionallystable. After heating, and while the consolidated mat is undercompression between the opposing air permeable belts, the layer ischilled by ambient air being applied equally on opposite sides of theconsolidated mat to, again, bring the thermal melt polymers back to asolid state.

Another illustrative embodiment of the present disclosure provides afire retardant board and method of making the same. An illustrativeembodiment of the board comprises a natural, synthetic, or blended fibermaterial that is formed into a board illustratively using one or more ofthe following: polyester, natural fiber, epoxy resin, phenol resin, dryor liquid urethane resins, polypropylene, and a fire retardant material.The resin is a binder that bonds the fibers into a board, while the fireretardant material makes the board less susceptible to flamedeformation. In an illustrative embodiment, the board can be a lowdensity board.

An illustrative embodiment of the disclosure provides a resonated fiberboard comprising an epoxy resin/fire retardant material combined with anatural and/or synthetic fiber material. For example, resin/fireretardant material can be added to a fiber mat comprising approximately85% natural fiber and approximately 15% polyester fiber. Anotherillustrative embodiment comprises an approximate 1100 gram per squaremeter (gsm) fiber mat. The mat is resonated with approximately a 50% to50% mix of epoxy resin and fire retardant powder. The amount ofresin/fire retardant material added is calculated by a percentage of thetotal weight of the mat as an add-on. For example, for the 1100 gsmfiber mat, a resin/powder add-on of approximately 35% is approximately385 gsm. In these illustrative examples, the binder may be Flexlok®epoxy resin with BanFlame®, a borate fire retardant powder. Theseproducts can be obtained from Ramcon Industries in Memphis, Tenn.Alternative flame resistant powders can be used, such as the Glo-Tard®fire resistance powder, a phosphate product available from Glo-TexManufacturing in Spartanburg, S.C.

In another illustrative embodiment, the board can be a 100% naturalfiber board. Such a board may increase the flame retardant properties,since the high calorie fuel source of the polyester and/or polypropyleneis eliminated. In yet another illustrative embodiment, polyester and/orpolypropylene or other synthetic fiber can be treated with a fireretardant additive, such as but not limited to approximately 5% bromideor phosphate fire retardant additive. These treated fibers can be mixedwith the natural fibers and the binder/powder add-on. In still anotherillustrative embodiment, the natural fibers can be treated with a fireretardant additive and then formed into a mat with the resin/fireretardant powder add-on. It is believed that such embodiments mayenhance the fire retardant properties. Further illustrative embodimentsmay include gram weights of mats ranging from approximately 300 gsm upto approximately 5000 gsm having ranges of dry or liquid urethaneresins, phenol or epoxy resin percentages from approximately 10% byweight up to approximately 45% by weight in combination of flameretardant ranging from approximately 45% additive down to approximately10% by weight, depending on the application requirement to meet certainbuilding codes or customer mandated requirements.

The following are illustrative resin/fire retardant powder formulationswhich were added to approximately 1100 gsm, 85% natural/15% polyesterfiber mats:

-   -   A. Flexlok® resin/BanFlame® FR powder. (˜35% add-on by weight)    -   B. Flexlok® resin/GloTard® LB9-4A FR powder. (˜35% add-on by        weight)    -   C. Flexlok® resin/GloTard® LB9-4A FR powder. (˜25% add-on by        weight)    -   D. Flexlok® resin/GloTard® LB9-4B FR powder. (˜25% add-on by        weight)    -   E. Flexlok® resin/GloTard® LB9-4B FR powder. (˜35% add-on by        weight)    -   F. Flexlok® resin/GloTard® LB9-4B FR powder. (˜51% add-on by        weight)        Samples A through F were subjected to a ASTM International Fire        Test E-84, and their results are as follows:

TABLE 1 A B C D E F Burn rate in mm 15.2 17.4 17.8 18.6 16.1 15.7 Burnlength in mm 228 260 267 279 241 235 after 60 seconds Afterflame in SESE 15 45 SE SE seconds SE = Self-Extinguishing

Without the inclusion of treated polyester or polypropylene fiber, theresults indicate that the composite control burn rate falls safelywithin the Class rating requirements as specified in UL E-84 burn ratecertification. Although self-extinguishing is not a specifiedrequirement to meet E-84, it nevertheless is another significantopportunity to improve fire safety, especially during containment.

Another test was conducted in accordance with the ASTM InternationalFire Test Response Standard E-84-03b, Surface Burning Characteristics ofBuilding Materials. This test is sometimes referred to as the SteinerTunnel Test. This test is applicable to exposed surfaces such as wallsand ceilings. The test was conducted with the specimen in the ceilingposition with the surface to be evaluated exposed face down to theignition source. The ASTM E-84 test method is believed technicallyidentical to NFPA No. 255 and UL No. 723. This standard is used tomeasure and describe the response of materials, products, or assembliesto heat and flame under controlled conditions.

The test provides comparative measurements of surface flame spread andsmoke development of materials with that of select grade red oak andfiber-reinforced cement board, Grade II, under specific fire exposureconditions. The test exposes a nominal 24-foot long by 20-inch wide testspecimen to a controlled air flow and a flaming fire which are adjustedto spread the flame along the entire length of a red oak specimen in5.50 minutes. During the 10-minute test duration, flame spread over thespecimen surface and density of the resulting smoke are measured andrecorded. Test results are calculated relative to red oak, which has anarbitrary rating of 100, and fiber-reinforced cement board, Grade II,which has a rating of 0.

The test results are expressed as flame spread index and smoke developedindex. The flame spread index is defined in ASTM E-176 as “a number ofclassification indicating a comparative measure derived fromobservations made during the progress of the boundary of a zone of flameunder defined test conditions.” The smoke developed index, a termspecific to ASTM E-84, is defined as “a number or classificationindicating a comparative measure derived from smoke obscuration datacollected during the test for surface burning characteristics.” It isbelieved that there is not necessarily a relationship between the twomeasurements. The method does not provide for measurement of heattransmission through the surface tested, the effect of aggravated flamespread behavior of an assembly resulting from the proximity ofcombustible walls and ceilings, or classifying a material asnoncombustible solely by means of a flame spread index. The zeroreference and other parameters critical to furnace operation areverified on the day of the test by conducting a 10-minute test using¼-inch fiber-reinforced cement board, Grade II. Periodic tests usingNOFMA certified 23/32-inch select grade red oak flooring provide datafor the 100 reference.

The test samples were fiber board substrates with epoxy resin/flameretardant material added thereto. Specifically, 22.5% epoxy resin, and22.5% fire retardant powder were added to approximately 935 grams ofnatural fiber and approximately 165 grams of polyester fiber. One testsample was a 35% resin/fire retardant powder add-on to the 1100 gsm mat,and the second was a 45% resin/fire retardant powder add-on to another1100 gsm mat. The material had a thickness of 0.327-inch. The materialwas conditioned to equilibrium in an atmosphere with the temperaturemaintained at 71+/−2 degrees F. and the relative humidity at 50+/−5percent. For testing, twelve pieces, each measuring 12″×48″ placed sideby side, were free laid over a 2-inch hexagonal wire mesh supported by¼-inch diameter steel rods spanning the ledges of the tunnel furnace at24-inch intervals. This method of auxiliary sample support is describedin Appendix X1 of the E-84 standard, Guide to Mounting Methods, SectionsX1.1.2.2 and X1.1.2.3.

The test results, calculated on the basis of observed flame propagationand the integrated area under the recorded smoke density curve, arepresented below. The flame spread index obtained in E-84 is rounded tothe nearest number divisible by five. Smoke developed indices arerounded to the nearest number divisible by five unless the Index isgreater than 200. In that case, the smoke developed index is rounded tothe nearest 50 points. The flame spread development data are alsopresented graphically below.

Specimen ignition over the burners occurred at 0.05 minute. Surfaceflame spread was observed to a maximum distance of 8.56 feet beyond thezero point at 1.75 minutes. The maximum temperature recorded during thetest was 593 degrees F.

The flame spread index and smoke developed index values obtained by ASTME-84 tests are frequently used by code officials and regulatory agenciesin the acceptance of interior finish materials for various applications.The most widely accepted classification system is described in theNational Fire Protection Association publication NFPA 101 Life SafetyCode, where:

Class A  0-25 flame spread index 0-450 smoke developed index Class B26-75 flame spread index 0-450 smoke developed index Class C 76-200flame spread index 0-450 smoke developed indexClass A, B, C corresponds to Type I, II, and III respectively in othercodes such as SBCCl, BOCA, and ICBG. They do not preclude a materialbeing otherwise classified by the authority of jurisdiction. The testresults were as follows and as shown in FIGS. 38 and 39:Sample 1: 35% resin/fire retardant powder add-onTime to ignition=00.05 minutesMaximum flame spread distance=08.56 feetTime to maximum spread=01.75 minutesFlame spread index=40Smoke developed index=25Sample 2: 45% resin/fire retardant powder add-onTime to Ignition=00.05 minutesMaximum Flamespread Distance=08.27 feetTime to Maximum Spread=02.07 minutes

Flame Spread Index=40 Smoke Developed Index=20

Both of these samples demonstrated a Class B flame spread and smokedeveloped index.

Another illustrative embodiment of this disclosure provides a board thathas a body impregnated with fire retardant material such as borate tocontrol the fire consumption of the body and a surface protectioncontrol to reduce combustibility thereon. The result of this is to offerflame retardant protection both internal to the board's body, as well asits surface. This provides combined protection to the board. Oneillustrative embodiment of such a board comprises a 1050 grm naturalfiber mat that included 20% epoxy (210 grin) and 20% borate (210 grm)impregnated into the mat and cured. In this embodiment the resultingboard becomes a 1470 grm board. Subsequently, a 5% liquid phosphatesolution illustratively comprising about 40% solids is applied to eachsurface of the board. In this case, a 183 grm liquid plus solidcomposition is applied to each side of the board. The 5% solutioncomprised about 73.5 grm dry solids including the fire retardantphosphate. A sample such as this was able to be rated Class A pursuantthe ASTM E-84-05 Surface Burning Characteristics of Building MaterialsTest. The results of such testing are represented below.

TABLE 2 SIDE CALCULATED CALCULATED TEST SAMPLE NO. EXPOSED SUPPORT FLAMESPREAD SMOKE DEVELOPED 1 NA WIRE & RODS 20.00 12.78 2 NA WIRE & RODS21.91 10.26 3 NA WIRE & RODS 20.17 13.36 SIDE FLAME SPREAD SMOKEDEVELOPED MATERIAL TESTED EXPOSED SUPPORT INDEX* INDEX* RED OAK FLOORING(calib) NA DECKS 100 100 REINFORCED CEMENT BOARD (calib) NA SELF 0 0Sample NA WIRE & RODS 20 10 *Flame Spread/Smoke Developed Index is theresult (or average of the results of multiple tests), rounded to thenearest multiple of 5. Smoke values in excess of 200, rounded to thenearest 50.

TABLE 3 TEST 1 ADC DRAFT (IN. H20)  0.082 GAS PRESS. (IN. H20)  0.289GAS VOL, (CF)  49.6 BTU/cf 998 SHUTTER  3″ TEMP. 13° BURIED 105° F. TESTMETHOD: ASTM E-84-05 MATERIAL SIZE: ⅜″ × 24″ × 96″ METHOD OF SUPPORT:WIRE & RODS REMARKS: IGNITION @: 34 MAX. FLAME FRONT 4.5′ @ 2:22 LIGHTBLUE FLAME FLAME SPREAD-  20.00 AREA UNDER THE  38.83 CURVE (MIN. FT.)SMOKE DEVELOPED-  12.78 TIME TIME DISTANCE # (Min.) (Sec.) (Ft.) 1 0 340.0 2 0 49 0.0 3 1 1 1.0 4 1 9 2.0 5 1 18 2.5 6 1 30 3.0 7 1 45 3.5 8 22 4.0 9 2 22 4.5 10 10 0 4.5 11 12 13 14 15 16 17 18 19 20

TABLE 4 TEST 2 ADC DRAFT (IN. H20)  0.082 GAS PRESS. (IN. H20)  0.284GAS VOL (CF)  49.58 BTU/cf 995 SHUTTER  3″ TEMP. 13° BURIED 105° F. TESTMETHOD: ASTM E-84-05 MATERIAL SIZE: ⅜″ × 24″ × 96″ METHOD OF SUPPORT:WIRE & RODS REMARKS: IGNITION @: 38 MAX. FLAME FRONT 5.0′ @ 2:20 LIGHTBLUE FLAME FLAME SPREAD-  21.91 AREA UNDER THE  42.54 CURVE (MIN. FT.)SMOKE DEVELOPED-  10.26 TIME TIME DISTANCE # (Min.) (Sec.) (Ft.) 1 0 380.0 2 0 52 0.0 3 1 5 1.0 4 1 11 2.0 5 1 25 2.5 6 1 36 3.0 7 1 49 3.5 8 158 4.0 9 2 9 4.5 10 2 20 5.0 11 10 0 5.0 12 13 14 15 18 17 18 19 20

TABLE 5 TEST 3 ADC DRAFT (IN. H20)  0.082 GAS PRESS. (IN. H20)  0.294GAS VOL, (CF)  49.67 BTU/cf 998 SHUTTER  3″ TEMP. 13° BURIED 105° F.TEST METHOD: ASTM E-84-05 MATERIAL SIZE: ⅜″ × 24″ × 96″ METHOD OFSUPPORT: WIRE & RODS REMARKS: IGNITION @: 33 MAX. FLAME FRONT 4.6′ @2:12 LIGHT BLUE FLAME FLAME SPREAD-  20.17 AREA UNDER THE  39.17 CURVE(MIN. FT.) SMOKE DEVELOPED-  13.36 TIME TIME DISTANCE # (Min.) (Sec.)(Ft.) 1 0 33 0.0 2 0 42 0.0 3 0 54 1.0 4 1 2 1.5 5 1 7 2.0 6 1 17 2.5 71 29 3.0 8 1 44 3.5 9 1 52 4.0 10 2 12 4.5 11 10 0 4.5 12 13 14 15 16 1718 19 20

Other embodiments that passed a Class A rating are those that included afire retardant surface coating using about 30% (solids) polyphosphateand about 37% (solids) liquid borate. It is appreciated from theseformulations that the more complete coverage of the surface by the fireretardant material there is, the better the surface protectioncharacteristics are. Illustratively ranges of the material and chemistrymakeup for illustrative fire retardant boards are provided in thefollowing Table 6;

TABLE 6 Illustrative Material and Chemistry Make Up Combinations forFire Retardant Boards Base weight of Mat Range Range pre Resin from toApplication gr/m² 600 2400 Composition of Basic Mat. Natural FiberTypes: % base wt. 20 100 Value in Product Jute Clean fiber, cut length,product all natural fiber mat. Tossa Clean fiber, cut length, produceall natural fiber mat. Kenal Domestic source, not available if cleanquality or cut length. Ramine Clean fiber, not available in cut length,week in tensile strength. Sisal Clean fiber, high natural stiffness,high fiber odor. Hemp Clean fiber, high tensile strength, high fiberodor. Flax Clean fiber, high fiber odor, residue Post fiber oil content.Treated Synthetic Fiber Types: % base wt. 0 20 Value in ProductFlamability Rayon Cellulous fiber, cut length, crimp to low improveprocessing, high absorbent rate. Polyester Polymer fiber, high pyrolisistemperature, medium crimp to improve processing. Nylon Polymer fiber,highest pyrolisis temperature, medium crimp to improve processingPolyethylene Polymer fiber, low pyrolisis temperature, high crimp toimprove processing. Polypropylene Polymer fiber, low pyrolisistemperature, high crimp to improve processing. Maximum Impregnation ofResin, Flame Retardant or a Combination of - 40% Impregnated Resin Rangefrom Range to Application post Mat. % of Base wgt. 5 40 Resin Types:Epoxy Pwdr Applied by air/vacuum. Epoxy Liquid Dip coated, sprayed orvacuum pulled. Urethane Dip coated, sprayed or vacuum pulled. Phenol Dipcoated, sprayed or vacuum pulled. Considered non viable due toformaldehyde off gas. Latex Dip coated, sprayed or vacuum pulled.Impregnate Flame % of Base Retardant post Mat. Weight 5 30 DegradingTemperature Flame control method Retarandant Borate above 300° F.Antimony water release, char forming Poly Phosphate above 300° F.Intumescent char forming. Ammonia above 300° F. Intumescent chlorine gasrelease, char forming. Phosphate Zince Borate above 400° F. Antimonychar forming. Surface Application of Flame Retardant Post Applied after% of Post Cure Range from Range to Resin Cure. Weight 10 30 DegradingTemperature Flame control method Retarandant Tetra Borate above 300° F.Antimony water release, char forming. Contains Types: LiquidPentahydride surfactant and adhesive in formulation Poly Phosphate above300° Intumescent char forming. Contains surfactant in formulation.Ammonia above 300° F. Intumescent chlorine gas release, char forming.Contains Phosphate surfactanat and adhesive in formulation. note: allsurface materials are illustratively liquid applied. Application can beachieved by Spray, Kiss Coating or Roll Coating. Spray application worksfor irregular surfaces. Fine droplets penetrate the deeper surface areaproviding full surface coverage. Surfactants are used to break downsurface tension of composite post cure to support rapid absorption ofliquid into cellulous materials. Non flammable adhesives are used toreduce post drying losses of retardants due to shipping, handling andassembly. Adhesives may also reduce drying time. Percent of activeretardant dry solids content in liquid range between 20% to 50%.

It is believed that the borate inside the interior or thickness of theboard expands when exposed to heat. As this happens the borate surroundsthe fibers in the board. Because the borate is non flammable, itprovides a barrier between the flame and the fibers. The borate may alsoshield the fibers from oxygen and heat. An embodiment of the disclosureincludes providing enough borate or other fire retardant material in theboard so the fire retardant material can protect the board and retardthe flame propagation.

The following illustrative powder resonating process to make such fireretardant mats comprises four primary components: 1) the powder feedingsystem, 2) the powder feed box, with overflow powder recycling, 3) abelt conveyor, and 4) an oven, an edge trim line, cross cutting andpackaging of sheeted product.

The powder feeding system is illustratively made up of 2 or more augerfeeders that disperse the powders via loss in weight screw augers orloss in weight feed belts pneumatically by transfer piping to the powderfeed box in the desired ratio and volume. The powder feed box dispersesthe powder(s) onto the substrate using negative pressure created by avacuum system. There is an upper chute where the powders are fed and thebelt conveyor is located there between to carry the substrate materialthrough the feed box. The vacuum system, located below, pulls thepowders through the substrate with the negative pressure. (This systemmay allow for as much as a 98% recovery of all unused powder and can berouted back into the delivery system.)

From the powder feed box, the resonated material proceeds on the beltconveyor through an oven to activate and cure the epoxy resin portion ofthe powder. Once the material exits the oven, the thermoset epoxy resinis cured and acts as polypropylene to transform the mat material into asemi-rigid board. The epoxy resin, however, may not be softened byre-heating like polypropylene, which is a thermoplastic resin.

An illustrative manufacturing process 800 of an illustrative embodimentof the fire retardant board is shown in a chart in FIG. 37. In theembodiment shown, a non-woven structural mat, is provided in rolled format 802. As shown at 804, the butt end of the roll is joined and stitchedto successive rolls to create a continuous line of matting. Materialaccumulator 806 assists in ensuring the continuous line of mattingthrough the process. This is particularly useful when rolls are requiredto be changed out. At 808, epoxy and borate powder is blown into thethickness of the mat from its top surface. In an illustrativeembodiment, not only is the powder blown onto the mat, but also a vacuumis applied under the mat to draw the powder farther into the thicknessof the mat. Furthermore, an illustrative loss in weight blending systemis used to feed any lost powder back through the system to be applied tothe mat later. The mat is then subjected to a first stage oven for resinsetting at reference numeral 810. Illustratively, this can be athree-meter top-down hot air oven for light curing. The curingtemperature is about 350° F. and the mat is subjected to thistemperature for about 30 seconds. The result is a partial cure to gel ofthe epoxy near the surface of the mat, as opposed to the core.

The mat is then flipped over 180° at 812 and more epoxy and boratepowder is applied top-down at 814. This step may also cause the mat toflatten out if any bowing occurred during the initial heat stage at 810.In this illustrative embodiment, powder that was lost during theoriginal application at 808 is fed through and applied to the mat at814. The mat is then subjected to a second stage resin curing process at816. At this stage, an illustrative six-meter oven with top-down andbottom-up hot air at about 350° F. cures the epoxy and borate. In oneillustrative embodiment, the mat is subjected to this temperature forone minute. In addition, this stage may also include a thickness controlwith finishing calendar rolls to control the thickness of the resultingboard. A top coat of liquid borate can be applied to one or bothsurfaces of the board illustratively using an off-line liquid storageand pump system. In another illustrative embodiment, there can be 7-10%solids with the balance being water, a surfactant, and/or an adhesive.At 820, the surface of the panel can be flashed dried. In an alternativeembodiment, and for esthetic purposes, an optional fast drying latexcoating can be applied to the surface of the board. Steps 824 through830 are conventional panel processing steps including edge trimming andsheet slitting along with cross-cutting, finishing, packaging, andlastly shipping at 830.

Another illustrative embodiment includes a triglycidyle isocyanurate(TGIC) polyester resin that may be used with the previously-describedfire-retardant formulations. The TGIC polyester resin includes calciumcarbonate and 1,3,5-Triglycidyle Isocyanurate. The fire-retardant/resincomponent previously described may be substituted with this resin. In anillustrative embodiment, the TGIC resin may be blended with a flameretardant such as sodium borate penta hydride. Both materials in powderform may have similar particle sizes which allow for homogenous mixing.In addition, the resin may have a first melting point of about 55degrees Celsius and a second melting point of about 85 degrees Celsius.This means that if the resin is exposed to a first heat application itmelts at the lower first melt temperature. If the resin is then exposedto a second heat application after cooling from the first heatapplication, the resin melts at the higher melt temperature. The resinmay fully cross link in about 10 minutes at about 150 degrees Celsius.In this time the endothermic reaction should be completed. The resin mayalso be used as an adhesive to bond the fibrous material together. Inalternative embodiments, variations of blend mixes combining TGIC resinwith sodium borate pentahydride may achieve desired end productmechanical values without compromising flame control. The amount ofsodium borate pentahydride application rate should not be less than 30%by weight of total product weight in order to maintain flame spreadcontrol. Total product weight includes the total weight of fibrous matalong with added TGIC resin weight. For example, a fibrous mat having apre-impregnation weight of about 1000 grams per square meter shouldinclude a TGIC resin application rate at about 20% of the fibrous matweight or about 200 grams per square meter. Accordingly, the totalfibrous mat weight impregnated with TGIC resin is about 1200 grams persquare meter. To achieve a Class A flame spread rating, it is believedthat at least 30% sodium borate pentahydride (e.g.,1200×1.3=1560−1200=360 grams active sodium borate) should be added tothe fibrous TGIC resin mat mixture.

In an illustrative embodiment, the application of sodium boratepentahydride may be applied in two parts. The first part includesdepositing the TGIC resin in powder form into the fibrous mat matrix. Inone embodiment, about 67% of the total sodium borate pentahydride isapplied this way. With the fibrous mat impregnated, the second part isapplying about 33% on the fibrous mat surface or surfaces using anaqueous mixture of dissolved sodium borate pentahydride which mayinclude about 40% dry solid load rate, about 1% surfactant to improvesurface wicking on aqueous mixture into mat matrix, about 1% watersoluble adhesive to promote binding of sodium borate pentahydride tofibrous matrix, and the balance water. In another embodiment, a blend ofepoxy powder resin may be used as a substitute for TGIC resin forapplications requiring higher heat exposures above 150 degrees Celsius.Amounts of TGIC or Epoxy resin may also depend on the product stiffnessrequirements. It is believed that amounts of resin may range from about5% to about 40% of the fibrous mat weight with about 20% applicationrate meeting many panel application requirements. This is because inaddition to providing flame spread control, liquid applied sodium boratepentahydride may add to board stiffness after re-crystallization.

An illustrative process of applying heat and time to adequately activatethe resin includes: providing a base fibrous mat having an illustrativeweight of about 1000 grams per square meter; applying a firstapplication of TGIC/sodium borate powder at a rate of about 200 gramsper square meter of total fibrous mat weight and heating the resin for30 seconds at 175 degrees Celsius using hot air recirculating ovens;applying a second application of TGIC/sodium borate powder on thereverse side of the fibrous mat at rate of 200 grams per square meter oftotal fibrous mat weight and heating the resin for about 60 seconds at175 degrees Celsius. The second heat application is longer than thefirst in order to achieve same cross linking values on the secondapplied resin as achieved by first application resin. Upon exiting ofthe second heat oven, the fibrous resin/borate matrix may beconsolidated illustratively using a dual belt compression press settingthe matrix final thickness, smoothening its surfaces and removing heatto allow the resins to solidify. This makes the resin a bindingadhesive. Upon exiting the dual belt press, the surface application ofsodium borate pentahydride is applied to one or both sides of the panel.The application can be achieved either using a surface spray applicator,or by using a foam generator system which foams the aqueous mix ofsodium borate pentahydride liquid into an applicable foam density,dispersing the foam onto the surface of the panel either on one side orboth sides. Illustratively, the foam may be designed to collapse withina short time (less than 5 seconds, for example) after it has beenapplied to the matrix surface. Controlling the rate of foam collapse mayallow the liquid solution to wick into the surface of the matrix andpenetrating the same before being exposed to hot air to solidify thesame prior to cutting and packaging. It can be appreciated that theprocess steps shown in the illustrative manufacturing process of FIG. 37can be analogous to this manufacturing process.

The following results are based on E-84 testing completed by NGC TestingServices, Buffalo N.Y.:

-   -   Flame Spread Index average of samples tested to date was about        16.90 (Class A).    -   Smoke generation average of samples tested to date was about        126.77 (Class A).        Illustratively, the fibrous mat may comprise about 85% natural        bast fiber and about 15% polyester tying fiber having gram        weights per square meter ranging from about 200 to about 1500.        Other ranges can be from about 50% to about 100% natural bast        fiber combined with a suitable synthetic fiber having a melt        temperature above about 200 degrees Celsius ranging from 0% up        to 50% of total weight. The TGIC or Epoxy powder resin may have        an application rate of about 20% or more of the total fibrous        mat weight. Other application rates may range from 5% up to 40%        of total fibrous mat weight. Powdered sodium borate pentahydride        application rate may be at least 20% of the total combined        weight of fibrous mat and applied resin. Another flame retardant        such as sodium borate deca-hydrate as well as other flame        retardants having similar activation temperatures and control        methods may work as well.

In another illustrative embodiment the TGIC polyester resin may alsoinclude a hardener additive that bonds with polyester to elevate thefirst and second melting point temperatures. The first melting point maybe about 55 degrees Celsius and the second melting point temperature maybe about 176 degrees Celsius. The TGIC polyester resin is a thermal setresin with catalyst blended in. An endothermic polymer is provided thatuses an exothermic source to trigger the chemical reaction.

In still another illustrative embodiment, sodium borate pentahydridepowder can be used to impregnate the mats of the type previouslydescribed. (See Table 6.) The sodium borate pentahydride powder used isa Neobor powder provided by U.S. Borax Company at 5 mol and containsB₂0₃, NA₂0, NA₂B407.5H₂0, chloride as CL, FE, and sulfate as S0₄. Also,is may be appreciated that although the TGIC polyester resin may providethe majority of a board's stiffness, the liquid borate application oneach surface of the board may also enhance that stiffness. The boratemay add stiffness as it transforms from a liquid to a solid with some ofthe liquid absorbing into the fiber cells where it recrystallizes.

Although the present disclosure has been described with reference toparticular means, materials and embodiments, from the foregoingdescription, one skilled in the art can easily ascertain the essentialcharacteristics of the present disclosure and various changes andmodifications may be made to adapt the various uses and characteristicswithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed:
 1. A method of manufacturing a fire retardantstructural board, the method comprising the steps of: (a) providing astructural mat constructed of randomly oriented fibrous material havinga weight, thickness, and first and second surfaces; (b) orienting thestructural mat to expose its first surface; (c) applying a firstapplication of at least one of polyester, epoxy resin, phenol resin,urethane or polypropylene binder and a fire retardant onto the firstsurface and into the thickness of the structural mat; (d) heating thestructural mat to only partially cure the binder applied onto the firstsurface; (e) turning the structural mat over to expose its secondsurface; (f) applying a second application of the binder and the fireretardant onto the second surface and into the thickness of thestructural mat; (g) heating the second surface of the structural mat tocure the binder applied onto the first and second surfaces andcompressing the mat to a desired thickness; and (h) coating the secondsurface of the structural mat with a liquid fire retardant composition;(i) flash drying the liquid composition wherein the resulting fireretardant structural board having a class A burn rate certification asspecified in the NFPA 101 life safety code or its equivalent; and (j)wherein steps are performed in sequential order: (a), (b), (c), (d),(e), (f), (g), (h), and (i).
 2. The method of manufacturing the fireretardant structural board of claim 1, wherein the binder istriglycidyle polyester which comprises calcium carbonate and1,3,5-triglycidyl isocyanurate.
 3. The method of manufacturing the fireretardant structural board of claim 1, wherein the fire retardant issodium borate pentahydride and is in an amount of about 30% or more ofthe total weight of the board.
 4. The method of manufacturing the fireretardant structural board of claim 1, wherein about 67% by weight ofthe fire retardant is dispersed between individual fibers throughout thethickness of the body, and wherein about 33% may be applied to at leastthe first surface of the body.
 5. The method of manufacturing the fireretardant structural board of claim 1, wherein the liquid fire retardantcomposition is an aqueous composition which also includes a surfactant,an adhesive, and water.
 6. The method of manufacturing the fireretardant structural board of claim 5, wherein the aqueous compositionfurther comprises about 40% sodium borate pentahydride as dry solids,about 1% surfactant, about 1% adhesive, and the balance water.
 7. Themethod of manufacturing the fire retardant structural board of claim 1,wherein the triglycidyl polyester binder is a resin formulated to beabout 5% to about 40% of the weight of the fibrous material.
 8. Themethod of manufacturing the fire retardant structural board of claim 1,wherein about 50% to about 100% is fibrous material, and comprises about0% to about 50% synthetic fiber having a melting temperature above about200 degrees.
 9. The fire retardant structural board of claim 1, whereinthe binder further comprises a hardener.
 10. A method of manufacturing afire retardant structural board, the method comprising the steps of: (a)providing a structural mat constructed of randomly oriented fibrousmaterial having a weight, thickness, and first and second surfaces; (b)orienting the structural mat to expose its first surface; (c) applying afirst application of at least one of polyester, epoxy resin, phenolresin, urethane or polypropylene binder and a fire retardant onto thefirst surface and into the thickness of the structural mat; (d) heatingthe structural mat to only partially cure the binder applied onto thefirst surface; (e) turning the structural mat over to expose its secondsurface; (f), applying a second application of the binder and the fireretardant onto the second surface and into the thickness of thestructural mat; (g) heating the second surface of the structural mat tocure the binder applied onto the first and second surfaces andcompressing the mat to a desired thickness; and (h) wherein steps areperformed in sequential order: (a), (b), (c), (d), (e), (f), and (g).11. A method of manufacturing a fire retardant structural board, themethod comprising the steps of: (a) providing a structural matconstructed of randomly oriented fibrous material having a weight,thickness, and first and second surfaces; (b) orienting the structuralmat to expose its first surface; (c) applying a first application of abinder and a fire retardant onto the first surface and into thethickness of the structural mat; (d) heating the structural mat to onlypartially cure the binder applied onto the first surface; (e) turningthe structural mat over to expose its second surface; (f) applying asecond application of the binder and the fire retardant onto the secondsurface and into the thickness of the structural mat; (g) heating thesecond surface of the structural mat to cure the binder applied onto thefirst and second surfaces and compressing the mat to a desiredthickness; and (h) wherein steps are performed in sequential order: (a),(b), (c), (d), (e), (f), and (g).
 12. The method of manufacturing thefire retardant structural board of claim 11, further comprising thesteps of applying the first application of binder and fire retardant ata rate of about 200 grams per square meter of total fibrous mat weight,and heating the mat for about 30 seconds at about 175 degrees Celsiususing a hot air recirculating oven.
 13. The method of manufacturing thefire retardant structural board of claim 12, further comprising thesteps of applying the second application of binder and fire retardantonto the second surface of the structural mat at rate of about 200 gramsper square meter of total fibrous mat weight, and heating the resin forabout 60 seconds at about 175 degrees Celsius.
 14. The method ofmanufacturing the fire retardant structural board of claim 11, furthercomprising the steps of cooling the structural mat after compressing andbefore coating.
 15. The method of manufacturing the fire retardantstructural board of claim 11, further comprising a step of coating thefirst surface of the structural mat with a liquid composition thatincludes sodium borate penta hydride.
 16. The method of manufacturingthe fire retardant structural board of claim 15, further comprising thestep of coating the first surface.
 17. The method of manufacturing thefire retardant structural board of claim 15, further comprising the stepof coating the first surface using a foam generator system which foams acomposition of sodium borate pentahydride liquid fire retardant into anapplicable foam density, and dispersing the foam onto the first surfacewhere the foam collapses at a rate that allows the composition to wickinto the surface of the mat.
 18. The method of manufacturing the fireretardant structural board of claim 11, further comprising the step ofwarming the first surface to solidify the composition.